[PATCH 6/6] virtio-blk: modernize sysfs attribute creation

Hannes Reinecke
2018-07-30T07:12:27Z

Use new-style DEVICE_ATTR_RO/DEVICE_ATTR_RW to create the sysfs attributes
and register the disk with default sysfs attribute groups.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Cc: Michael Tsirkin <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
---
drivers/block/virtio_blk.c | 68 ++++++++++++++++++++++++++--------------------
1 file changed, 39 insertions(+), 29 deletions(-)

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index fe80560000a1..086c6bb12baa 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -351,8 +351,8 @@ static int minor_to_index(int minor)
return minor >> PART_BITS;
}

-static ssize_t virtblk_serial_show(struct device *dev,
- struct device_attribute *attr, char *buf)
+static ssize_t serial_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
{
struct gendisk *disk = dev_to_disk(dev);
int err;
@@ -371,7 +371,7 @@ static ssize_t virtblk_serial_show(struct device *dev,
return err;
}

-static DEVICE_ATTR(serial, 0444, virtblk_serial_show, NULL);
+static DEVICE_ATTR_RO(serial);

/* The queue's logical block size must be set before calling this */
static void virtblk_update_capacity(struct virtio_blk *vblk, bool resize)
@@ -545,8 +545,8 @@ static const char *const virtblk_cache_types[] = {
};

static ssize_t
-virtblk_cache_type_store(struct device *dev, struct device_attribute *attr,
- const char *buf, size_t count)
+cache_type_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
{
struct gendisk *disk = dev_to_disk(dev);
struct virtio_blk *vblk = disk->private_data;
@@ -564,8 +564,7 @@ virtblk_cache_type_store(struct device *dev, struct device_attribute *attr,
}

static ssize_t
-virtblk_cache_type_show(struct device *dev, struct device_attribute *attr,
- char *buf)
+cache_type_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct gendisk *disk = dev_to_disk(dev);
struct virtio_blk *vblk = disk->private_data;
@@ -575,12 +574,38 @@ virtblk_cache_type_show(struct device *dev, struct device_attribute *attr,
return snprintf(buf, 40, "%s\n", virtblk_cache_types[writeback]);
}

-static const struct device_attribute dev_attr_cache_type_ro =
- __ATTR(cache_type, 0444,
- virtblk_cache_type_show, NULL);
-static const struct device_attribute dev_attr_cache_type_rw =
- __ATTR(cache_type, 0644,
- virtblk_cache_type_show, virtblk_cache_type_store);
+static DEVICE_ATTR_RW(cache_type);
+
+static struct attribute *virtblk_attrs[] = {
+ &dev_attr_serial.attr,
+ &dev_attr_cache_type.attr,
+ NULL,
+};
+
+static umode_t virtblk_attrs_are_visible(struct kobject *kobj,
+ struct attribute *a, int n)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct gendisk *disk = dev_to_disk(dev);
+ struct virtio_blk *vblk = disk->private_data;
+ struct virtio_device *vdev = vblk->vdev;
+
+ if (a == &dev_attr_cache_type.attr &&
+ !virtio_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE))
+ return S_IRUGO;
+
+ return a->mode;
+}
+
+static const struct attribute_group virtblk_attr_group = {
+ .attrs = virtblk_attrs,
+ .is_visible = virtblk_attrs_are_visible,
+};
+
+static const struct attribute_group *virtblk_attr_groups[] = {
+ &virtblk_attr_group,
+ NULL,
+};

static int virtblk_init_request(struct blk_mq_tag_set *set, struct request *rq,
unsigned int hctx_idx, unsigned int numa_node)
@@ -780,24 +805,9 @@ static int virtblk_probe(struct virtio_device *vdev)
virtblk_update_capacity(vblk, false);
virtio_device_ready(vdev);

- device_add_disk(&vdev->dev, vblk->disk, NULL);
- err = device_create_file(disk_to_dev(vblk->disk), &dev_attr_serial);
- if (err)
- goto out_del_disk;
-
- if (virtio_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE))
- err = device_create_file(disk_to_dev(vblk->disk),
- &dev_attr_cache_type_rw);
- else
- err = device_create_file(disk_to_dev(vblk->disk),
- &dev_attr_cache_type_ro);
- if (err)
- goto out_del_disk;
+ device_add_disk(&vdev->dev, vblk->disk, virtblk_attr_groups);
return 0;

-out_del_disk:
- del_gendisk(vblk->disk);
- blk_cleanup_queue(vblk->disk->queue);
out_free_tags:
blk_mq_free_tag_set(&vblk->tag_set);
out_put_disk:
--
2.12.3