[PATCH][next] mips: sgi-ip22: Replace "s[n]?printf" with sysfs_emit in sysfs callbacks

From: Paulo Miguel Almeida
Date: Mon Oct 14 2024 - 17:00:06 EST


snprintf() has the documented, but still rather strange trait of
returning the length of the data that *would have been* written to the
array if space were available, rather than the arguably more useful
length of data *actually* written, it is usually considered wise to use
scnprintf()/vscnprintf() instead. In the case of sysfs call-backs,
new wrappers exist that do just that while also being PAGE_SIZE aware

This patch updates the sysfs .show() callbacks to use the sysfs_emit()
helper instead of snprintf() and sprintf().

Link: https://lwn.net/Articles/69419/
Link: https://github.com/KSPP/linux/issues/105
Signed-off-by: Paulo Miguel Almeida <paulo.miguel.almeida.rodenas@xxxxxxxxx>
---
arch/mips/sgi-ip22/ip22-gio.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/arch/mips/sgi-ip22/ip22-gio.c b/arch/mips/sgi-ip22/ip22-gio.c
index d20eec742bfa..5893ea4e382c 100644
--- a/arch/mips/sgi-ip22/ip22-gio.c
+++ b/arch/mips/sgi-ip22/ip22-gio.c
@@ -165,9 +165,8 @@ static ssize_t modalias_show(struct device *dev, struct device_attribute *a,
char *buf)
{
struct gio_device *gio_dev = to_gio_device(dev);
- int len = snprintf(buf, PAGE_SIZE, "gio:%x\n", gio_dev->id.id);

- return (len >= PAGE_SIZE) ? (PAGE_SIZE - 1) : len;
+ return sysfs_emit(buf, "gio:%x\n", gio_dev->id.id);
}
static DEVICE_ATTR_RO(modalias);

@@ -177,7 +176,7 @@ static ssize_t name_show(struct device *dev,
struct gio_device *giodev;

giodev = to_gio_device(dev);
- return sprintf(buf, "%s", giodev->name);
+ return sysfs_emit(buf, "%s\n", giodev->name);
}
static DEVICE_ATTR_RO(name);

@@ -187,7 +186,7 @@ static ssize_t id_show(struct device *dev,
struct gio_device *giodev;

giodev = to_gio_device(dev);
- return sprintf(buf, "%x", giodev->id.id);
+ return sysfs_emit(buf, "%x\n", giodev->id.id);
}
static DEVICE_ATTR_RO(id);

--
2.47.0