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

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

[Qing Wang]

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@vivo.com>
---
 fs/xfs/xfs_sysfs.c | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/fs/xfs/xfs_sysfs.c b/fs/xfs/xfs_sysfs.c
index f1bc88f..3c171bf 100644
--- a/fs/xfs/xfs_sysfs.c
+++ b/fs/xfs/xfs_sysfs.c
@@ -104,7 +104,7 @@ bug_on_assert_show(
 	struct kobject		*kobject,
 	char			*buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%d\n", xfs_globals.bug_on_assert ? 1 : 0);
+	return sysfs_emit(buf, "%d\n", xfs_globals.bug_on_assert ? 1 : 0);
 }
 XFS_SYSFS_ATTR_RW(bug_on_assert);
 
@@ -134,7 +134,7 @@ log_recovery_delay_show(
 	struct kobject	*kobject,
 	char		*buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%d\n", xfs_globals.log_recovery_delay);
+	return sysfs_emit(buf, "%d\n", xfs_globals.log_recovery_delay);
 }
 XFS_SYSFS_ATTR_RW(log_recovery_delay);
 
@@ -164,7 +164,7 @@ mount_delay_show(
 	struct kobject	*kobject,
 	char		*buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%d\n", xfs_globals.mount_delay);
+	return sysfs_emit(buf, "%d\n", xfs_globals.mount_delay);
 }
 XFS_SYSFS_ATTR_RW(mount_delay);
 
@@ -187,7 +187,7 @@ always_cow_show(
 	struct kobject	*kobject,
 	char		*buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%d\n", xfs_globals.always_cow);
+	return sysfs_emit(buf, "%d\n", xfs_globals.always_cow);
 }
 XFS_SYSFS_ATTR_RW(always_cow);
 
@@ -223,7 +223,7 @@ pwork_threads_show(
 	struct kobject	*kobject,
 	char		*buf)
 {
-	return snprintf(buf, PAGE_SIZE, "%d\n", xfs_globals.pwork_threads);
+	return sysfs_emit(buf, "%d\n", xfs_globals.pwork_threads);
 }
 XFS_SYSFS_ATTR_RW(pwork_threads);
 #endif /* DEBUG */
@@ -326,7 +326,7 @@ log_head_lsn_show(
 	block = log->l_curr_block;
 	spin_unlock(&log->l_icloglock);
 
-	return snprintf(buf, PAGE_SIZE, "%d:%d\n", cycle, block);
+	return sysfs_emit(buf, "%d:%d\n", cycle, block);
 }
 XFS_SYSFS_ATTR_RO(log_head_lsn);
 
@@ -340,7 +340,7 @@ log_tail_lsn_show(
 	struct xlog *log = to_xlog(kobject);
 
 	xlog_crack_atomic_lsn(&log->l_tail_lsn, &cycle, &block);
-	return snprintf(buf, PAGE_SIZE, "%d:%d\n", cycle, block);
+	return sysfs_emit(buf, "%d:%d\n", cycle, block);
 }
 XFS_SYSFS_ATTR_RO(log_tail_lsn);
 
@@ -355,7 +355,7 @@ reserve_grant_head_show(
 	struct xlog *log = to_xlog(kobject);
 
 	xlog_crack_grant_head(&log->l_reserve_head.grant, &cycle, &bytes);
-	return snprintf(buf, PAGE_SIZE, "%d:%d\n", cycle, bytes);
+	return sysfs_emit(buf, "%d:%d\n", cycle, bytes);
 }
 XFS_SYSFS_ATTR_RO(reserve_grant_head);
 
@@ -369,7 +369,7 @@ write_grant_head_show(
 	struct xlog *log = to_xlog(kobject);
 
 	xlog_crack_grant_head(&log->l_write_head.grant, &cycle, &bytes);
-	return snprintf(buf, PAGE_SIZE, "%d:%d\n", cycle, bytes);
+	return sysfs_emit(buf, "%d:%d\n", cycle, bytes);
 }
 XFS_SYSFS_ATTR_RO(write_grant_head);
 
@@ -424,7 +424,7 @@ max_retries_show(
 	else
 		retries = cfg->max_retries;
 
-	return snprintf(buf, PAGE_SIZE, "%d\n", retries);
+	return sysfs_emit(buf, "%d\n", retries);
 }
 
 static ssize_t
@@ -465,7 +465,7 @@ retry_timeout_seconds_show(
 	else
 		timeout = jiffies_to_msecs(cfg->retry_timeout) / MSEC_PER_SEC;
 
-	return snprintf(buf, PAGE_SIZE, "%d\n", timeout);
+	return sysfs_emit(buf, "%d\n", timeout);
 }
 
 static ssize_t
@@ -503,7 +503,7 @@ fail_at_unmount_show(
 {
 	struct xfs_mount	*mp = err_to_mp(kobject);
 
-	return snprintf(buf, PAGE_SIZE, "%d\n", mp->m_fail_unmount);
+	return sysfs_emit(buf, "%d\n", mp->m_fail_unmount);
 }
 
 static ssize_t
-- 
2.7.4

Re: [PATCH] xfs: replace snprintf in show functions with sysfs_emit

[Darrick J. Wong]

On Tue, Oct 12, 2021 at 08:29:31PM -0700, Qing Wang wrote:
> 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@vivo.com>

This seems like a fairly straightforward conversion.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>

--D

> ---
>  fs/xfs/xfs_sysfs.c | 24 ++++++++++++------------
>  1 file changed, 12 insertions(+), 12 deletions(-)
> 
> diff --git a/fs/xfs/xfs_sysfs.c b/fs/xfs/xfs_sysfs.c
> index f1bc88f..3c171bf 100644
> --- a/fs/xfs/xfs_sysfs.c
> +++ b/fs/xfs/xfs_sysfs.c
> @@ -104,7 +104,7 @@ bug_on_assert_show(
>  	struct kobject		*kobject,
>  	char			*buf)
>  {
> -	return snprintf(buf, PAGE_SIZE, "%d\n", xfs_globals.bug_on_assert ? 1 : 0);
> +	return sysfs_emit(buf, "%d\n", xfs_globals.bug_on_assert ? 1 : 0);
>  }
>  XFS_SYSFS_ATTR_RW(bug_on_assert);
>  
> @@ -134,7 +134,7 @@ log_recovery_delay_show(
>  	struct kobject	*kobject,
>  	char		*buf)
>  {
> -	return snprintf(buf, PAGE_SIZE, "%d\n", xfs_globals.log_recovery_delay);
> +	return sysfs_emit(buf, "%d\n", xfs_globals.log_recovery_delay);
>  }
>  XFS_SYSFS_ATTR_RW(log_recovery_delay);
>  
> @@ -164,7 +164,7 @@ mount_delay_show(
>  	struct kobject	*kobject,
>  	char		*buf)
>  {
> -	return snprintf(buf, PAGE_SIZE, "%d\n", xfs_globals.mount_delay);
> +	return sysfs_emit(buf, "%d\n", xfs_globals.mount_delay);
>  }
>  XFS_SYSFS_ATTR_RW(mount_delay);
>  
> @@ -187,7 +187,7 @@ always_cow_show(
>  	struct kobject	*kobject,
>  	char		*buf)
>  {
> -	return snprintf(buf, PAGE_SIZE, "%d\n", xfs_globals.always_cow);
> +	return sysfs_emit(buf, "%d\n", xfs_globals.always_cow);
>  }
>  XFS_SYSFS_ATTR_RW(always_cow);
>  
> @@ -223,7 +223,7 @@ pwork_threads_show(
>  	struct kobject	*kobject,
>  	char		*buf)
>  {
> -	return snprintf(buf, PAGE_SIZE, "%d\n", xfs_globals.pwork_threads);
> +	return sysfs_emit(buf, "%d\n", xfs_globals.pwork_threads);
>  }
>  XFS_SYSFS_ATTR_RW(pwork_threads);
>  #endif /* DEBUG */
> @@ -326,7 +326,7 @@ log_head_lsn_show(
>  	block = log->l_curr_block;
>  	spin_unlock(&log->l_icloglock);
>  
> -	return snprintf(buf, PAGE_SIZE, "%d:%d\n", cycle, block);
> +	return sysfs_emit(buf, "%d:%d\n", cycle, block);
>  }
>  XFS_SYSFS_ATTR_RO(log_head_lsn);
>  
> @@ -340,7 +340,7 @@ log_tail_lsn_show(
>  	struct xlog *log = to_xlog(kobject);
>  
>  	xlog_crack_atomic_lsn(&log->l_tail_lsn, &cycle, &block);
> -	return snprintf(buf, PAGE_SIZE, "%d:%d\n", cycle, block);
> +	return sysfs_emit(buf, "%d:%d\n", cycle, block);
>  }
>  XFS_SYSFS_ATTR_RO(log_tail_lsn);
>  
> @@ -355,7 +355,7 @@ reserve_grant_head_show(
>  	struct xlog *log = to_xlog(kobject);
>  
>  	xlog_crack_grant_head(&log->l_reserve_head.grant, &cycle, &bytes);
> -	return snprintf(buf, PAGE_SIZE, "%d:%d\n", cycle, bytes);
> +	return sysfs_emit(buf, "%d:%d\n", cycle, bytes);
>  }
>  XFS_SYSFS_ATTR_RO(reserve_grant_head);
>  
> @@ -369,7 +369,7 @@ write_grant_head_show(
>  	struct xlog *log = to_xlog(kobject);
>  
>  	xlog_crack_grant_head(&log->l_write_head.grant, &cycle, &bytes);
> -	return snprintf(buf, PAGE_SIZE, "%d:%d\n", cycle, bytes);
> +	return sysfs_emit(buf, "%d:%d\n", cycle, bytes);
>  }
>  XFS_SYSFS_ATTR_RO(write_grant_head);
>  
> @@ -424,7 +424,7 @@ max_retries_show(
>  	else
>  		retries = cfg->max_retries;
>  
> -	return snprintf(buf, PAGE_SIZE, "%d\n", retries);
> +	return sysfs_emit(buf, "%d\n", retries);
>  }
>  
>  static ssize_t
> @@ -465,7 +465,7 @@ retry_timeout_seconds_show(
>  	else
>  		timeout = jiffies_to_msecs(cfg->retry_timeout) / MSEC_PER_SEC;
>  
> -	return snprintf(buf, PAGE_SIZE, "%d\n", timeout);
> +	return sysfs_emit(buf, "%d\n", timeout);
>  }
>  
>  static ssize_t
> @@ -503,7 +503,7 @@ fail_at_unmount_show(
>  {
>  	struct xfs_mount	*mp = err_to_mp(kobject);
>  
> -	return snprintf(buf, PAGE_SIZE, "%d\n", mp->m_fail_unmount);
> +	return sysfs_emit(buf, "%d\n", mp->m_fail_unmount);
>  }
>  
>  static ssize_t
> -- 
> 2.7.4
> 

Re: [PATCH] xfs: replace snprintf in show functions with sysfs_emit

[Joe Perches]

On Tue, 2021-10-12 at 20:29 -0700, Qing Wang wrote:
> 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.
[]
> diff --git a/fs/xfs/xfs_sysfs.c b/fs/xfs/xfs_sysfs.c
[]
> @@ -104,7 +104,7 @@ bug_on_assert_show(
>  	struct kobject		*kobject,
>  	char			*buf)
>  {
> -	return snprintf(buf, PAGE_SIZE, "%d\n", xfs_globals.bug_on_assert ? 1 : 0);
> +	return sysfs_emit(buf, "%d\n", xfs_globals.bug_on_assert ? 1 : 0);

trivia:

The ?: is not necessary as xfs_globals.bug_on_assert is a bool
and would have an implicit cast done.

	return sysfs_emit(buf, "%d\n", xfs_globals.bug_on_assert);