xen-pciback: Use sysfs_emit_at() in slots_show() and irq_handlers_show()

[PATCH] xen-pciback: Use sysfs_emit_at() in slots_show() and irq_handlers_show()

Posted by Ryan Chung 3 months, 2 weeks ago

Replace the use of scnprintf() with sysfs_emit_at() in slots_show() and irq_handlers_show().

This change uses sysfs_emit() API usage for sysfs 'show'
functions as recommended from Documentation/filesystems/sysfs.rst. 

No functional change intended.

Signed-off-by: Ryan Chung <seokwoo.chung130@gmail.com>
---
 drivers/xen/xen-pciback/pci_stub.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c
index 5c2f829d5b0b..d0a889474a46 100644
--- a/drivers/xen/xen-pciback/pci_stub.c
+++ b/drivers/xen/xen-pciback/pci_stub.c
@@ -18,6 +18,7 @@
 #include <linux/wait.h>
 #include <linux/sched.h>
 #include <linux/atomic.h>
+#include <linux/sysfs.h>
 #include <xen/events.h>
 #include <xen/pci.h>
 #include <xen/xen.h>
@@ -30,6 +31,7 @@
 #include "conf_space.h"
 #include "conf_space_quirks.h"
 
+
 #define PCISTUB_DRIVER_NAME "pciback"
 
 static char *pci_devs_to_hide;
@@ -720,7 +722,7 @@ static void kill_domain_by_device(struct pcistub_device *psdev)
 		return;
 	}
 	/*PV AER handlers will set this flag*/
-	xenbus_printf(xbt, nodename, "aerState" , "aerfail");
+	xenbus_printf(xbt, nodename, "aerState", "aerfail");
 	err = xenbus_transaction_end(xbt, 0);
 	if (err) {
 		if (err == -EAGAIN)
@@ -1261,7 +1263,7 @@ static ssize_t slots_show(struct device_driver *drv, char *buf)
 		if (count >= PAGE_SIZE)
 			break;
 
-		count += scnprintf(buf + count, PAGE_SIZE - count,
+			count += sysfs_emit_at(buf, count,
 				   "%04x:%02x:%02x.%d\n",
 				   pci_dev_id->domain, pci_dev_id->bus,
 				   PCI_SLOT(pci_dev_id->devfn),
@@ -1290,7 +1292,7 @@ static ssize_t irq_handlers_show(struct device_driver *drv, char *buf)
 		if (!dev_data)
 			continue;
 		count +=
-		    scnprintf(buf + count, PAGE_SIZE - count,
+		    sysfs_emit_at(buf, count,
 			      "%s:%s:%sing:%ld\n",
 			      pci_name(psdev->dev),
 			      dev_data->isr_on ? "on" : "off",
-- 
2.43.0

Re: [PATCH] xen-pciback: Use sysfs_emit_at() in slots_show() and irq_handlers_show()

Posted by Ryan Chung 3 months, 2 weeks ago

I sent the wrong patch. My apologies. Please ignore this patch. I will
send a V2 shortly.

On Tue, 24 Jun 2025 at 12:26, Ryan Chung <seokwoo.chung130@gmail.com> wrote:
>
> Replace the use of scnprintf() with sysfs_emit_at() in slots_show() and irq_handlers_show().
>
> This change uses sysfs_emit() API usage for sysfs 'show'
> functions as recommended from Documentation/filesystems/sysfs.rst.
>
> No functional change intended.
>
> Signed-off-by: Ryan Chung <seokwoo.chung130@gmail.com>
> ---
>  drivers/xen/xen-pciback/pci_stub.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c
> index 5c2f829d5b0b..d0a889474a46 100644
> --- a/drivers/xen/xen-pciback/pci_stub.c
> +++ b/drivers/xen/xen-pciback/pci_stub.c
> @@ -18,6 +18,7 @@
>  #include <linux/wait.h>
>  #include <linux/sched.h>
>  #include <linux/atomic.h>
> +#include <linux/sysfs.h>
>  #include <xen/events.h>
>  #include <xen/pci.h>
>  #include <xen/xen.h>
> @@ -30,6 +31,7 @@
>  #include "conf_space.h"
>  #include "conf_space_quirks.h"
>
> +
>  #define PCISTUB_DRIVER_NAME "pciback"
>
>  static char *pci_devs_to_hide;
> @@ -720,7 +722,7 @@ static void kill_domain_by_device(struct pcistub_device *psdev)
>                 return;
>         }
>         /*PV AER handlers will set this flag*/
> -       xenbus_printf(xbt, nodename, "aerState" , "aerfail");
> +       xenbus_printf(xbt, nodename, "aerState", "aerfail");
>         err = xenbus_transaction_end(xbt, 0);
>         if (err) {
>                 if (err == -EAGAIN)
> @@ -1261,7 +1263,7 @@ static ssize_t slots_show(struct device_driver *drv, char *buf)
>                 if (count >= PAGE_SIZE)
>                         break;
>
> -               count += scnprintf(buf + count, PAGE_SIZE - count,
> +                       count += sysfs_emit_at(buf, count,
>                                    "%04x:%02x:%02x.%d\n",
>                                    pci_dev_id->domain, pci_dev_id->bus,
>                                    PCI_SLOT(pci_dev_id->devfn),
> @@ -1290,7 +1292,7 @@ static ssize_t irq_handlers_show(struct device_driver *drv, char *buf)
>                 if (!dev_data)
>                         continue;
>                 count +=
> -                   scnprintf(buf + count, PAGE_SIZE - count,
> +                   sysfs_emit_at(buf, count,
>                               "%s:%s:%sing:%ld\n",
>                               pci_name(psdev->dev),
>                               dev_data->isr_on ? "on" : "off",
> --
> 2.43.0
>