[PATCH linux-next] net: atm: Convert to use sysfs_emit()/sysfs_emit_at() APIs

[PATCH linux-next] net: atm: Convert to use sysfs_emit()/sysfs_emit_at() APIs

[zhangsongyi.cgel]

From: zhang songyi <zhang.songyi@zte.com.cn>

Follow the advice of the Documentation/filesystems/sysfs.rst and show()
should only use sysfs_emit() or sysfs_emit_at() when formatting the value
to be returned to user space.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: zhang songyi <zhang.songyi@zte.com.cn>
---
 net/atm/atm_sysfs.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/net/atm/atm_sysfs.c b/net/atm/atm_sysfs.c
index 0fdbdfd19474..2258d94288a6 100644
--- a/net/atm/atm_sysfs.c
+++ b/net/atm/atm_sysfs.c
@@ -16,7 +16,7 @@ static ssize_t type_show(struct device *cdev,
 {
 	struct atm_dev *adev = to_atm_dev(cdev);
 
-	return scnprintf(buf, PAGE_SIZE, "%s\n", adev->type);
+	return sysfs_emit(buf, "%s\n", adev->type);
 }
 
 static ssize_t address_show(struct device *cdev,
@@ -24,7 +24,7 @@ static ssize_t address_show(struct device *cdev,
 {
 	struct atm_dev *adev = to_atm_dev(cdev);
 
-	return scnprintf(buf, PAGE_SIZE, "%pM\n", adev->esi);
+	return sysfs_emit(buf, "%pM\n", adev->esi);
 }
 
 static ssize_t atmaddress_show(struct device *cdev,
@@ -37,7 +37,7 @@ static ssize_t atmaddress_show(struct device *cdev,
 
 	spin_lock_irqsave(&adev->lock, flags);
 	list_for_each_entry(aaddr, &adev->local, entry) {
-		count += scnprintf(buf + count, PAGE_SIZE - count,
+		count += sysfs_emit_at(buf, count,
 				   "%1phN.%2phN.%10phN.%6phN.%1phN\n",
 				   &aaddr->addr.sas_addr.prv[0],
 				   &aaddr->addr.sas_addr.prv[1],
@@ -55,7 +55,7 @@ static ssize_t atmindex_show(struct device *cdev,
 {
 	struct atm_dev *adev = to_atm_dev(cdev);
 
-	return scnprintf(buf, PAGE_SIZE, "%d\n", adev->number);
+	return sysfs_emit(buf, "%d\n", adev->number);
 }
 
 static ssize_t carrier_show(struct device *cdev,
@@ -63,7 +63,7 @@ static ssize_t carrier_show(struct device *cdev,
 {
 	struct atm_dev *adev = to_atm_dev(cdev);
 
-	return scnprintf(buf, PAGE_SIZE, "%d\n",
+	return sysfs_emit(buf, "%d\n",
 			 adev->signal == ATM_PHY_SIG_LOST ? 0 : 1);
 }
 
@@ -87,7 +87,7 @@ static ssize_t link_rate_show(struct device *cdev,
 	default:
 		link_rate = adev->link_rate * 8 * 53;
 	}
-	return scnprintf(buf, PAGE_SIZE, "%d\n", link_rate);
+	return sysfs_emit(buf, "%d\n", link_rate);
 }
 
 static DEVICE_ATTR_RO(address);
-- 
2.25.1

Re: [PATCH linux-next] net: atm: Convert to use sysfs_emit()/sysfs_emit_at() APIs

[Jakub Kicinski]

On Tue, 27 Sep 2022 06:46:49 +0000 zhangsongyi.cgel@gmail.com wrote:
> From: zhang songyi <zhang.songyi@zte.com.cn>
> 
> Follow the advice of the Documentation/filesystems/sysfs.rst and show()
> should only use sysfs_emit() or sysfs_emit_at() when formatting the value
> to be returned to user space.

Is there an end goal to this? If the code is correct let's leave 
it as is. ATM is hopefully going to be deleted soon.

Re: [PATCH linux-next] net: atm: Convert to use sysfs_emit()/sysfs_emit_at() APIs

[Joe Perches]

On Tue, 2022-09-27 at 07:01 -0700, Jakub Kicinski wrote:
> On Tue, 27 Sep 2022 06:46:49 +0000 zhangsongyi.cgel@gmail.com wrote:
> > From: zhang songyi <zhang.songyi@zte.com.cn>
> > 
> > Follow the advice of the Documentation/filesystems/sysfs.rst and show()
> > should only use sysfs_emit() or sysfs_emit_at() when formatting the value
> > to be returned to user space.
> 
> Is there an end goal to this?

To make it easier to validate all other kernel uses of
sprintf/snprintf/scnprintf.

> If the code is correct let's leave 
> it as is. ATM is hopefully going to be deleted soon.

<shrug>  The code is correct as-is.