[PATCH] ext4: replace snprintf in show functions with sysfs_emit

From: Qing Wang
Date: Tue Oct 12 2021 - 23:29:09 EST


coccicheck complains about the use of snprintf() in sysfs show functions.

Fix the coccicheck warning:
WARNING: use scnprintf or sprintf.

Use sysfs_emit instead of scnprintf or sprintf makes more sense.

Signed-off-by: Qing Wang <wangqing@xxxxxxxx>
---
fs/ext4/sysfs.c | 34 +++++++++++++++++-----------------
1 file changed, 17 insertions(+), 17 deletions(-)

diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c
index 2314f74..2a4ae3d 100644
--- a/fs/ext4/sysfs.c
+++ b/fs/ext4/sysfs.c
@@ -63,7 +63,7 @@ static ssize_t session_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)
{
struct super_block *sb = sbi->s_buddy_cache->i_sb;

- return snprintf(buf, PAGE_SIZE, "%lu\n",
+ return sysfs_emit(buf, "%lu\n",
(part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
sbi->s_sectors_written_start) >> 1);
}
@@ -72,7 +72,7 @@ static ssize_t lifetime_write_kbytes_show(struct ext4_sb_info *sbi, char *buf)
{
struct super_block *sb = sbi->s_buddy_cache->i_sb;

- return snprintf(buf, PAGE_SIZE, "%llu\n",
+ return sysfs_emit(buf, "%llu\n",
(unsigned long long)(sbi->s_kbytes_written +
((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
EXT4_SB(sb)->s_sectors_written_start) >> 1)));
@@ -130,8 +130,8 @@ static ssize_t trigger_test_error(struct ext4_sb_info *sbi,
static ssize_t journal_task_show(struct ext4_sb_info *sbi, char *buf)
{
if (!sbi->s_journal)
- return snprintf(buf, PAGE_SIZE, "<none>\n");
- return snprintf(buf, PAGE_SIZE, "%d\n",
+ return sysfs_emit(buf, "<none>\n");
+ return sysfs_emit(buf, "%d\n",
task_pid_vnr(sbi->s_journal->j_task));
}

@@ -357,7 +357,7 @@ static void *calc_ptr(struct ext4_attr *a, struct ext4_sb_info *sbi)

static ssize_t __print_tstamp(char *buf, __le32 lo, __u8 hi)
{
- return snprintf(buf, PAGE_SIZE, "%lld\n",
+ return sysfs_emit(buf, "%lld\n",
((time64_t)hi << 32) + le32_to_cpu(lo));
}

@@ -374,7 +374,7 @@ static ssize_t ext4_attr_show(struct kobject *kobj,

switch (a->attr_id) {
case attr_delayed_allocation_blocks:
- return snprintf(buf, PAGE_SIZE, "%llu\n",
+ return sysfs_emit(buf, "%llu\n",
(s64) EXT4_C2B(sbi,
percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
case attr_session_write_kbytes:
@@ -382,11 +382,11 @@ static ssize_t ext4_attr_show(struct kobject *kobj,
case attr_lifetime_write_kbytes:
return lifetime_write_kbytes_show(sbi, buf);
case attr_reserved_clusters:
- return snprintf(buf, PAGE_SIZE, "%llu\n",
+ return sysfs_emit(buf, "%llu\n",
(unsigned long long)
atomic64_read(&sbi->s_resv_clusters));
case attr_sra_exceeded_retry_limit:
- return snprintf(buf, PAGE_SIZE, "%llu\n",
+ return sysfs_emit(buf, "%llu\n",
(unsigned long long)
percpu_counter_sum(&sbi->s_sra_exceeded_retry_limit));
case attr_inode_readahead:
@@ -394,42 +394,42 @@ static ssize_t ext4_attr_show(struct kobject *kobj,
if (!ptr)
return 0;
if (a->attr_ptr == ptr_ext4_super_block_offset)
- return snprintf(buf, PAGE_SIZE, "%u\n",
+ return sysfs_emit(buf, "%u\n",
le32_to_cpup(ptr));
else
- return snprintf(buf, PAGE_SIZE, "%u\n",
+ return sysfs_emit(buf, "%u\n",
*((unsigned int *) ptr));
case attr_pointer_ul:
if (!ptr)
return 0;
- return snprintf(buf, PAGE_SIZE, "%lu\n",
+ return sysfs_emit(buf, "%lu\n",
*((unsigned long *) ptr));
case attr_pointer_u8:
if (!ptr)
return 0;
- return snprintf(buf, PAGE_SIZE, "%u\n",
+ return sysfs_emit(buf, "%u\n",
*((unsigned char *) ptr));
case attr_pointer_u64:
if (!ptr)
return 0;
if (a->attr_ptr == ptr_ext4_super_block_offset)
- return snprintf(buf, PAGE_SIZE, "%llu\n",
+ return sysfs_emit(buf, "%llu\n",
le64_to_cpup(ptr));
else
- return snprintf(buf, PAGE_SIZE, "%llu\n",
+ return sysfs_emit(buf, "%llu\n",
*((unsigned long long *) ptr));
case attr_pointer_string:
if (!ptr)
return 0;
- return snprintf(buf, PAGE_SIZE, "%.*s\n", a->attr_size,
+ return sysfs_emit(buf, "%.*s\n", a->attr_size,
(char *) ptr);
case attr_pointer_atomic:
if (!ptr)
return 0;
- return snprintf(buf, PAGE_SIZE, "%d\n",
+ return sysfs_emit(buf, "%d\n",
atomic_read((atomic_t *) ptr));
case attr_feature:
- return snprintf(buf, PAGE_SIZE, "supported\n");
+ return sysfs_emit(buf, "supported\n");
case attr_first_error_time:
return print_tstamp(buf, sbi->s_es, s_first_error_time);
case attr_last_error_time:
--
2.7.4