nvme: register ns_id attributes as default sysfs groups

We should be registering the ns_id attribute as default sysfs
attribute groups, otherwise we have a race condition between
the uevent and the attributes appearing in sysfs.

Suggested-by: Bart van Assche <bvanassche@acm.org>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 44 insertions, 61 deletions

diff --git a/drivers/nvme/host/lightnvm.c b/drivers/nvme/host/lightnvm.c
index 6fe5923c95d4..1e4f97538838 100644
--- a/drivers/nvme/host/lightnvm.c
+++ b/drivers/nvme/host/lightnvm.c
@@ -1190,10 +1190,29 @@ static NVM_DEV_ATTR_12_RO(multiplane_modes);
 static NVM_DEV_ATTR_12_RO(media_capabilities);
 static NVM_DEV_ATTR_12_RO(max_phys_secs);
 
-static struct attribute *nvm_dev_attrs_12[] = {
+/* 2.0 values */
+static NVM_DEV_ATTR_20_RO(groups);
+static NVM_DEV_ATTR_20_RO(punits);
+static NVM_DEV_ATTR_20_RO(chunks);
+static NVM_DEV_ATTR_20_RO(clba);
+static NVM_DEV_ATTR_20_RO(ws_min);
+static NVM_DEV_ATTR_20_RO(ws_opt);
+static NVM_DEV_ATTR_20_RO(maxoc);
+static NVM_DEV_ATTR_20_RO(maxocpu);
+static NVM_DEV_ATTR_20_RO(mw_cunits);
+static NVM_DEV_ATTR_20_RO(write_typ);
+static NVM_DEV_ATTR_20_RO(write_max);
+static NVM_DEV_ATTR_20_RO(reset_typ);
+static NVM_DEV_ATTR_20_RO(reset_max);
+
+static struct attribute *nvm_dev_attrs[] = {
+	/* version agnostic attrs */
 	&dev_attr_version.attr,
 	&dev_attr_capabilities.attr,
+	&dev_attr_read_typ.attr,
+	&dev_attr_read_max.attr,
 
+	/* 1.2 attrs */
 	&dev_attr_vendor_opcode.attr,
 	&dev_attr_device_mode.attr,
 	&dev_attr_media_manager.attr,
@@ -1208,8 +1227,6 @@ static struct attribute *nvm_dev_attrs_12[] = {
 	&dev_attr_page_size.attr,
 	&dev_attr_hw_sector_size.attr,
 	&dev_attr_oob_sector_size.attr,
-	&dev_attr_read_typ.attr,
-	&dev_attr_read_max.attr,
 	&dev_attr_prog_typ.attr,
 	&dev_attr_prog_max.attr,
 	&dev_attr_erase_typ.attr,
@@ -1218,33 +1235,7 @@ static struct attribute *nvm_dev_attrs_12[] = {
 	&dev_attr_media_capabilities.attr,
 	&dev_attr_max_phys_secs.attr,
 
-	NULL,
-};
-
-static const struct attribute_group nvm_dev_attr_group_12 = {
-	.name		= "lightnvm",
-	.attrs		= nvm_dev_attrs_12,
-};
-
-/* 2.0 values */
-static NVM_DEV_ATTR_20_RO(groups);
-static NVM_DEV_ATTR_20_RO(punits);
-static NVM_DEV_ATTR_20_RO(chunks);
-static NVM_DEV_ATTR_20_RO(clba);
-static NVM_DEV_ATTR_20_RO(ws_min);
-static NVM_DEV_ATTR_20_RO(ws_opt);
-static NVM_DEV_ATTR_20_RO(maxoc);
-static NVM_DEV_ATTR_20_RO(maxocpu);
-static NVM_DEV_ATTR_20_RO(mw_cunits);
-static NVM_DEV_ATTR_20_RO(write_typ);
-static NVM_DEV_ATTR_20_RO(write_max);
-static NVM_DEV_ATTR_20_RO(reset_typ);
-static NVM_DEV_ATTR_20_RO(reset_max);
-
-static struct attribute *nvm_dev_attrs_20[] = {
-	&dev_attr_version.attr,
-	&dev_attr_capabilities.attr,
-
+	/* 2.0 attrs */
 	&dev_attr_groups.attr,
 	&dev_attr_punits.attr,
 	&dev_attr_chunks.attr,
@@ -1255,8 +1246,6 @@ static struct attribute *nvm_dev_attrs_20[] = {
 	&dev_attr_maxocpu.attr,
 	&dev_attr_mw_cunits.attr,
 
-	&dev_attr_read_typ.attr,
-	&dev_attr_read_max.attr,
 	&dev_attr_write_typ.attr,
 	&dev_attr_write_max.attr,
 	&dev_attr_reset_typ.attr,
@@ -1265,44 +1254,38 @@ static struct attribute *nvm_dev_attrs_20[] = {
 	NULL,
 };
 
-static const struct attribute_group nvm_dev_attr_group_20 = {
-	.name		= "lightnvm",
-	.attrs		= nvm_dev_attrs_20,
-};
-
-int nvme_nvm_register_sysfs(struct nvme_ns *ns)
+static umode_t nvm_dev_attrs_visible(struct kobject *kobj,
+				     struct attribute *attr, int index)
 {
+	struct device *dev = container_of(kobj, struct device, kobj);
+	struct gendisk *disk = dev_to_disk(dev);
+	struct nvme_ns *ns = disk->private_data;
 	struct nvm_dev *ndev = ns->ndev;
-	struct nvm_geo *geo = &ndev->geo;
+	struct device_attribute *dev_attr =
+		container_of(attr, typeof(*dev_attr), attr);
 
 	if (!ndev)
-		return -EINVAL;
-
-	switch (geo->major_ver_id) {
-	case 1:
-		return sysfs_create_group(&disk_to_dev(ns->disk)->kobj,
-					&nvm_dev_attr_group_12);
-	case 2:
-		return sysfs_create_group(&disk_to_dev(ns->disk)->kobj,
-					&nvm_dev_attr_group_20);
-	}
-
-	return -EINVAL;
-}
+		return 0;
 
-void nvme_nvm_unregister_sysfs(struct nvme_ns *ns)
-{
-	struct nvm_dev *ndev = ns->ndev;
-	struct nvm_geo *geo = &ndev->geo;
+	if (dev_attr->show == nvm_dev_attr_show)
+		return attr->mode;
 
-	switch (geo->major_ver_id) {
+	switch (ndev->geo.major_ver_id) {
 	case 1:
-		sysfs_remove_group(&disk_to_dev(ns->disk)->kobj,
-					&nvm_dev_attr_group_12);
+		if (dev_attr->show == nvm_dev_attr_show_12)
+			return attr->mode;
 		break;
 	case 2:
-		sysfs_remove_group(&disk_to_dev(ns->disk)->kobj,
-					&nvm_dev_attr_group_20);
+		if (dev_attr->show == nvm_dev_attr_show_20)
+			return attr->mode;
 		break;
 	}
+
+	return 0;
 }
+
+const struct attribute_group nvme_nvm_attr_group = {
+	.name		= "lightnvm",
+	.attrs		= nvm_dev_attrs,
+	.is_visible	= nvm_dev_attrs_visible,
+};