PCI: Use scnprintf(), not snprintf(), in sysfs "show" functions

Sysfs "show" methods should return the number of bytes printed into the
buffer.  This is the return value of scnprintf() [1].

snprintf(buf, size, ...) prints at most "size" bytes into "buf", but
returns the number of bytes that *would* be printed if "buf" were large
enough.

Replace use of snprintf() with scnprintf().  No functional change intended.

Related:
  https://patchwork.kernel.org/patch/9946759/#20969333
  https://lwn.net/Articles/69419

[1] Documentation/filesystems/sysfs.rst

[bhelgaas: squashed, commit log]
Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20200824233918.26306-2-kw@linux.com
Link: https://lore.kernel.org/r/20200824233918.26306-3-kw@linux.com
Link: https://lore.kernel.org/r/20200824233918.26306-4-kw@linux.comSigned-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/p2pdma.c

@@ -53,7 +53,7 @@ static ssize_t size_show(struct device *dev, struct device_attribute *attr,
 	if (pdev->p2pdma->pool)
 		size = gen_pool_size(pdev->p2pdma->pool);
 
-	return snprintf(buf, PAGE_SIZE, "%zd\n", size);
+	return scnprintf(buf, PAGE_SIZE, "%zd\n", size);
 }
 static DEVICE_ATTR_RO(size);
 
@@ -66,7 +66,7 @@ static ssize_t available_show(struct device *dev, struct device_attribute *attr,
 	if (pdev->p2pdma->pool)
 		avail = gen_pool_avail(pdev->p2pdma->pool);
 
-	return snprintf(buf, PAGE_SIZE, "%zd\n", avail);
+	return scnprintf(buf, PAGE_SIZE, "%zd\n", avail);
 }
 static DEVICE_ATTR_RO(available);
 
@@ -75,8 +75,8 @@ static ssize_t published_show(struct device *dev, struct device_attribute *attr,
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
 
-	return snprintf(buf, PAGE_SIZE, "%d\n",
-			pdev->p2pdma->p2pmem_published);
+	return scnprintf(buf, PAGE_SIZE, "%d\n",
+			 pdev->p2pdma->p2pmem_published);
 }
 static DEVICE_ATTR_RO(published);
 

drivers/pci/pci-sysfs.c

@@ -574,7 +574,7 @@ static ssize_t driver_override_show(struct device *dev,
 	ssize_t len;
 
 	device_lock(dev);
-	len = snprintf(buf, PAGE_SIZE, "%s\n", pdev->driver_override);
+	len = scnprintf(buf, PAGE_SIZE, "%s\n", pdev->driver_override);
 	device_unlock(dev);
 	return len;
 }

drivers/pci/pci.c

@@ -6347,7 +6347,7 @@ static ssize_t resource_alignment_show(struct bus_type *bus, char *buf)
 
 	spin_lock(&resource_alignment_lock);
 	if (resource_alignment_param)
-		count = snprintf(buf, PAGE_SIZE, "%s", resource_alignment_param);
+		count = scnprintf(buf, PAGE_SIZE, "%s", resource_alignment_param);
 	spin_unlock(&resource_alignment_lock);
 
 	/*