[PATCH v2 04/10] PCI/AER: Hide the "aer" sysfs directory when AER is unavailable

[Yazen Ghannam]

aer_attr_group is a named group, so sysfs creates an "aer" directory for
every PCI device. aer_attrs_are_visible() hides the attributes when the
device has no aer_info, but internal_create_group() only skips the
directory when is_visible() returns SYSFS_GROUP_INVISIBLE for the first
attribute. The result is an empty /sys/bus/pci/devices/*/aer/ on every
device without AER.

Switch to DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE(), which returns
SYSFS_GROUP_INVISIBLE when the group predicate is false. Drop the
per-attribute callback, since all four attributes share one condition.

aer_stats_attr_group is unnamed and creates no directory, so it is left
alone.

Fixes: b4fe7398def6 ("PCI/AER: Add sysfs attributes for log ratelimits")
Reported-by: Sashiko <sashiko-bot@xxxxxxxxxx>
Closes: https://lore.kernel.org/linux-pci/20260714191826.BA81E1F000E9@xxxxxxxxxxxxxxx/
Assisted-by: LLM
Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
---
 drivers/pci/pcie/aer.c | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
index 5498fc605556..91d73bd2ca7c 100644
--- a/drivers/pci/pcie/aer.c
+++ b/drivers/pci/pcie/aer.c
@@ -777,22 +777,19 @@ static struct attribute *aer_attrs[] = {
 	NULL
 };
 
-static umode_t aer_attrs_are_visible(struct kobject *kobj,
-				     struct attribute *a, int n)
+static bool aer_group_visible(struct kobject *kobj)
 {
-	struct device *dev = kobj_to_dev(kobj);
-	struct pci_dev *pdev = to_pci_dev(dev);
+	struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj));
 
-	if (!pdev->aer_info)
-		return 0;
-
-	return a->mode;
+	return !!pdev->aer_info;
 }
 
+DEFINE_SIMPLE_SYSFS_GROUP_VISIBLE(aer);
+
 const struct attribute_group aer_attr_group = {
 	.name = "aer",
 	.attrs = aer_attrs,
-	.is_visible = aer_attrs_are_visible,
+	.is_visible = SYSFS_GROUP_VISIBLE(aer),
 };
 
 static void pci_dev_aer_stats_incr(struct pci_dev *pdev,
-- 
2.43.0