fs/gfs2/sys.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-)
Documentation/filesystems/sysfs.rst mentions that show() should only
use sysfs_emit() or sysfs_emit_at() when formatting values returned
to user space. This patch updates the GFS2 sysfs interface accordingly.
It replaces uses of sprintf() and snprintf() in all *_show() functions
with sysfs_emit() to align with current kernel sysfs API best practices.
It also updates the GFS2_SHOW_UINT macro to use sysfs_emit() instead
of snprintf().
Signed-off-by: Utkarsh Singh <utkarsh.singh.em@gmail.com>
---
v1 --> v2: Code style cleanup and maintainer updates
fs/gfs2/sys.c | 32 ++++++++++++++++----------------
1 file changed, 16 insertions(+), 16 deletions(-)
diff --git a/fs/gfs2/sys.c b/fs/gfs2/sys.c
index c3c8842920d2..487fff098465 100644
--- a/fs/gfs2/sys.c
+++ b/fs/gfs2/sys.c
@@ -59,7 +59,7 @@ static struct kset *gfs2_kset;
static ssize_t id_show(struct gfs2_sbd *sdp, char *buf)
{
- return snprintf(buf, PAGE_SIZE, "%u:%u\n",
+ return sysfs_emit(buf, "%u:%u\n",
MAJOR(sdp->sd_vfs->s_dev), MINOR(sdp->sd_vfs->s_dev));
}
@@ -68,7 +68,7 @@ static ssize_t status_show(struct gfs2_sbd *sdp, char *buf)
unsigned long f = sdp->sd_flags;
ssize_t s;
- s = snprintf(buf, PAGE_SIZE,
+ s = sysfs_emit(buf,
"Journal Checked: %d\n"
"Journal Live: %d\n"
"Journal ID: %d\n"
@@ -140,7 +140,7 @@ static ssize_t status_show(struct gfs2_sbd *sdp, char *buf)
static ssize_t fsname_show(struct gfs2_sbd *sdp, char *buf)
{
- return snprintf(buf, PAGE_SIZE, "%s\n", sdp->sd_fsname);
+ return sysfs_emit(buf, "%s\n", sdp->sd_fsname);
}
static ssize_t uuid_show(struct gfs2_sbd *sdp, char *buf)
@@ -150,7 +150,7 @@ static ssize_t uuid_show(struct gfs2_sbd *sdp, char *buf)
buf[0] = '\0';
if (uuid_is_null(&s->s_uuid))
return 0;
- return snprintf(buf, PAGE_SIZE, "%pUB\n", &s->s_uuid);
+ return sysfs_emit(buf, "%pUB\n", &s->s_uuid);
}
static ssize_t freeze_show(struct gfs2_sbd *sdp, char *buf)
@@ -158,7 +158,7 @@ static ssize_t freeze_show(struct gfs2_sbd *sdp, char *buf)
struct super_block *sb = sdp->sd_vfs;
int frozen = (sb->s_writers.frozen == SB_UNFROZEN) ? 0 : 1;
- return snprintf(buf, PAGE_SIZE, "%d\n", frozen);
+ return sysfs_emit(buf, "%d\n", frozen);
}
static ssize_t freeze_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
@@ -194,7 +194,7 @@ static ssize_t freeze_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
static ssize_t withdraw_show(struct gfs2_sbd *sdp, char *buf)
{
unsigned int b = gfs2_withdrawing_or_withdrawn(sdp);
- return snprintf(buf, PAGE_SIZE, "%u\n", b);
+ return sysfs_emit(buf, "%u\n", b);
}
static ssize_t withdraw_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
@@ -397,7 +397,7 @@ static struct kobj_type gfs2_ktype = {
static ssize_t proto_name_show(struct gfs2_sbd *sdp, char *buf)
{
const struct lm_lockops *ops = sdp->sd_lockstruct.ls_ops;
- return sprintf(buf, "%s\n", ops->lm_proto_name);
+ return sysfs_emit(buf, "%s\n", ops->lm_proto_name);
}
static ssize_t block_show(struct gfs2_sbd *sdp, char *buf)
@@ -408,7 +408,7 @@ static ssize_t block_show(struct gfs2_sbd *sdp, char *buf)
if (test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))
val = 1;
- ret = sprintf(buf, "%d\n", val);
+ ret = sysfs_emit(buf, "%d\n", val);
return ret;
}
@@ -437,7 +437,7 @@ static ssize_t wdack_show(struct gfs2_sbd *sdp, char *buf)
{
int val = completion_done(&sdp->sd_wdack) ? 1 : 0;
- return sprintf(buf, "%d\n", val);
+ return sysfs_emit(buf, "%d\n", val);
}
static ssize_t wdack_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
@@ -459,7 +459,7 @@ static ssize_t wdack_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
static ssize_t lkfirst_show(struct gfs2_sbd *sdp, char *buf)
{
struct lm_lockstruct *ls = &sdp->sd_lockstruct;
- return sprintf(buf, "%d\n", ls->ls_first);
+ return sysfs_emit(buf, "%d\n", ls->ls_first);
}
static ssize_t lkfirst_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
@@ -492,7 +492,7 @@ static ssize_t lkfirst_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
static ssize_t first_done_show(struct gfs2_sbd *sdp, char *buf)
{
struct lm_lockstruct *ls = &sdp->sd_lockstruct;
- return sprintf(buf, "%d\n", !!test_bit(DFL_FIRST_MOUNT_DONE, &ls->ls_recover_flags));
+ return sysfs_emit(buf, "%d\n", !!test_bit(DFL_FIRST_MOUNT_DONE, &ls->ls_recover_flags));
}
int gfs2_recover_set(struct gfs2_sbd *sdp, unsigned jid)
@@ -550,18 +550,18 @@ static ssize_t recover_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
static ssize_t recover_done_show(struct gfs2_sbd *sdp, char *buf)
{
struct lm_lockstruct *ls = &sdp->sd_lockstruct;
- return sprintf(buf, "%d\n", ls->ls_recover_jid_done);
+ return sysfs_emit(buf, "%d\n", ls->ls_recover_jid_done);
}
static ssize_t recover_status_show(struct gfs2_sbd *sdp, char *buf)
{
struct lm_lockstruct *ls = &sdp->sd_lockstruct;
- return sprintf(buf, "%d\n", ls->ls_recover_jid_status);
+ return sysfs_emit(buf, "%d\n", ls->ls_recover_jid_status);
}
static ssize_t jid_show(struct gfs2_sbd *sdp, char *buf)
{
- return sprintf(buf, "%d\n", sdp->sd_lockstruct.ls_jid);
+ return sysfs_emit(buf, "%d\n", sdp->sd_lockstruct.ls_jid);
}
static ssize_t jid_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
@@ -626,7 +626,7 @@ static struct attribute *lock_module_attrs[] = {
static ssize_t quota_scale_show(struct gfs2_sbd *sdp, char *buf)
{
- return snprintf(buf, PAGE_SIZE, "%u %u\n",
+ return sysfs_emit(buf, "%u %u\n",
sdp->sd_tune.gt_quota_scale_num,
sdp->sd_tune.gt_quota_scale_den);
}
@@ -679,7 +679,7 @@ static struct gfs2_attr tune_attr_##name = __ATTR(name, 0644, show, store)
#define TUNE_ATTR_2(name, store) \
static ssize_t name##_show(struct gfs2_sbd *sdp, char *buf) \
{ \
- return snprintf(buf, PAGE_SIZE, "%u\n", sdp->sd_tune.gt_##name); \
+ return sysfs_emit(buf, "%u\n", sdp->sd_tune.gt_##name); \
} \
TUNE_ATTR_3(name, name##_show, store)
--
2.43.0On Mon, Sep 22, 2025 at 7:53 PM Utkarsh Singh
<utkarsh.singh.em@gmail.com> wrote:
> Documentation/filesystems/sysfs.rst mentions that show() should only
> use sysfs_emit() or sysfs_emit_at() when formatting values returned
> to user space. This patch updates the GFS2 sysfs interface accordingly.
>
> It replaces uses of sprintf() and snprintf() in all *_show() functions
> with sysfs_emit() to align with current kernel sysfs API best practices.
I've applied that part. I'm not pushing this into the upcoming merge
window anymore, though.
> It also updates the GFS2_SHOW_UINT macro to use sysfs_emit() instead
> of snprintf().
Huh, what's that?
> Signed-off-by: Utkarsh Singh <utkarsh.singh.em@gmail.com>
> ---
> v1 --> v2: Code style cleanup and maintainer updates
>
> fs/gfs2/sys.c | 32 ++++++++++++++++----------------
> 1 file changed, 16 insertions(+), 16 deletions(-)
>
> diff --git a/fs/gfs2/sys.c b/fs/gfs2/sys.c
> index c3c8842920d2..487fff098465 100644
> --- a/fs/gfs2/sys.c
> +++ b/fs/gfs2/sys.c
> @@ -59,7 +59,7 @@ static struct kset *gfs2_kset;
>
> static ssize_t id_show(struct gfs2_sbd *sdp, char *buf)
> {
> - return snprintf(buf, PAGE_SIZE, "%u:%u\n",
> + return sysfs_emit(buf, "%u:%u\n",
> MAJOR(sdp->sd_vfs->s_dev), MINOR(sdp->sd_vfs->s_dev));
> }
>
> @@ -68,7 +68,7 @@ static ssize_t status_show(struct gfs2_sbd *sdp, char *buf)
> unsigned long f = sdp->sd_flags;
> ssize_t s;
>
> - s = snprintf(buf, PAGE_SIZE,
> + s = sysfs_emit(buf,
> "Journal Checked: %d\n"
> "Journal Live: %d\n"
> "Journal ID: %d\n"
> @@ -140,7 +140,7 @@ static ssize_t status_show(struct gfs2_sbd *sdp, char *buf)
>
> static ssize_t fsname_show(struct gfs2_sbd *sdp, char *buf)
> {
> - return snprintf(buf, PAGE_SIZE, "%s\n", sdp->sd_fsname);
> + return sysfs_emit(buf, "%s\n", sdp->sd_fsname);
> }
>
> static ssize_t uuid_show(struct gfs2_sbd *sdp, char *buf)
> @@ -150,7 +150,7 @@ static ssize_t uuid_show(struct gfs2_sbd *sdp, char *buf)
> buf[0] = '\0';
> if (uuid_is_null(&s->s_uuid))
> return 0;
> - return snprintf(buf, PAGE_SIZE, "%pUB\n", &s->s_uuid);
> + return sysfs_emit(buf, "%pUB\n", &s->s_uuid);
> }
>
> static ssize_t freeze_show(struct gfs2_sbd *sdp, char *buf)
> @@ -158,7 +158,7 @@ static ssize_t freeze_show(struct gfs2_sbd *sdp, char *buf)
> struct super_block *sb = sdp->sd_vfs;
> int frozen = (sb->s_writers.frozen == SB_UNFROZEN) ? 0 : 1;
>
> - return snprintf(buf, PAGE_SIZE, "%d\n", frozen);
> + return sysfs_emit(buf, "%d\n", frozen);
> }
>
> static ssize_t freeze_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
> @@ -194,7 +194,7 @@ static ssize_t freeze_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
> static ssize_t withdraw_show(struct gfs2_sbd *sdp, char *buf)
> {
> unsigned int b = gfs2_withdrawing_or_withdrawn(sdp);
> - return snprintf(buf, PAGE_SIZE, "%u\n", b);
> + return sysfs_emit(buf, "%u\n", b);
> }
>
> static ssize_t withdraw_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
> @@ -397,7 +397,7 @@ static struct kobj_type gfs2_ktype = {
> static ssize_t proto_name_show(struct gfs2_sbd *sdp, char *buf)
> {
> const struct lm_lockops *ops = sdp->sd_lockstruct.ls_ops;
> - return sprintf(buf, "%s\n", ops->lm_proto_name);
> + return sysfs_emit(buf, "%s\n", ops->lm_proto_name);
> }
>
> static ssize_t block_show(struct gfs2_sbd *sdp, char *buf)
> @@ -408,7 +408,7 @@ static ssize_t block_show(struct gfs2_sbd *sdp, char *buf)
>
> if (test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))
> val = 1;
> - ret = sprintf(buf, "%d\n", val);
> + ret = sysfs_emit(buf, "%d\n", val);
> return ret;
> }
>
> @@ -437,7 +437,7 @@ static ssize_t wdack_show(struct gfs2_sbd *sdp, char *buf)
> {
> int val = completion_done(&sdp->sd_wdack) ? 1 : 0;
>
> - return sprintf(buf, "%d\n", val);
> + return sysfs_emit(buf, "%d\n", val);
> }
>
> static ssize_t wdack_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
> @@ -459,7 +459,7 @@ static ssize_t wdack_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
> static ssize_t lkfirst_show(struct gfs2_sbd *sdp, char *buf)
> {
> struct lm_lockstruct *ls = &sdp->sd_lockstruct;
> - return sprintf(buf, "%d\n", ls->ls_first);
> + return sysfs_emit(buf, "%d\n", ls->ls_first);
> }
>
> static ssize_t lkfirst_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
> @@ -492,7 +492,7 @@ static ssize_t lkfirst_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
> static ssize_t first_done_show(struct gfs2_sbd *sdp, char *buf)
> {
> struct lm_lockstruct *ls = &sdp->sd_lockstruct;
> - return sprintf(buf, "%d\n", !!test_bit(DFL_FIRST_MOUNT_DONE, &ls->ls_recover_flags));
> + return sysfs_emit(buf, "%d\n", !!test_bit(DFL_FIRST_MOUNT_DONE, &ls->ls_recover_flags));
> }
>
> int gfs2_recover_set(struct gfs2_sbd *sdp, unsigned jid)
> @@ -550,18 +550,18 @@ static ssize_t recover_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
> static ssize_t recover_done_show(struct gfs2_sbd *sdp, char *buf)
> {
> struct lm_lockstruct *ls = &sdp->sd_lockstruct;
> - return sprintf(buf, "%d\n", ls->ls_recover_jid_done);
> + return sysfs_emit(buf, "%d\n", ls->ls_recover_jid_done);
> }
>
> static ssize_t recover_status_show(struct gfs2_sbd *sdp, char *buf)
> {
> struct lm_lockstruct *ls = &sdp->sd_lockstruct;
> - return sprintf(buf, "%d\n", ls->ls_recover_jid_status);
> + return sysfs_emit(buf, "%d\n", ls->ls_recover_jid_status);
> }
>
> static ssize_t jid_show(struct gfs2_sbd *sdp, char *buf)
> {
> - return sprintf(buf, "%d\n", sdp->sd_lockstruct.ls_jid);
> + return sysfs_emit(buf, "%d\n", sdp->sd_lockstruct.ls_jid);
> }
>
> static ssize_t jid_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
> @@ -626,7 +626,7 @@ static struct attribute *lock_module_attrs[] = {
>
> static ssize_t quota_scale_show(struct gfs2_sbd *sdp, char *buf)
> {
> - return snprintf(buf, PAGE_SIZE, "%u %u\n",
> + return sysfs_emit(buf, "%u %u\n",
> sdp->sd_tune.gt_quota_scale_num,
> sdp->sd_tune.gt_quota_scale_den);
> }
> @@ -679,7 +679,7 @@ static struct gfs2_attr tune_attr_##name = __ATTR(name, 0644, show, store)
> #define TUNE_ATTR_2(name, store) \
> static ssize_t name##_show(struct gfs2_sbd *sdp, char *buf) \
> { \
> - return snprintf(buf, PAGE_SIZE, "%u\n", sdp->sd_tune.gt_##name); \
> + return sysfs_emit(buf, "%u\n", sdp->sd_tune.gt_##name); \
> } \
> TUNE_ATTR_3(name, name##_show, store)
>
> --
> 2.43.0
>
Thanks,
Andreas
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