[PATCH 2/5] block: genhd: add device_add_disk_with_groups

Hannes Reinecke
2018-07-25T06:28:37Z

Update __device_add_disk() to take an 'groups' argument so that
individual drivers can register a device with additional sysfs
attributes.
This avoids race condition the driver would otherwise have if these
groups need to be created with sysfs_add_groups().

Signed-off-by: Martin Wilck <martin.wilck@suse.com>
Signed-off-by: Hannes Reinecke <hare@suse.com>
---
block/genhd.c | 28 +++++++++++++++++++++++-----
include/linux/genhd.h | 3 +++
2 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/block/genhd.c b/block/genhd.c
index cfa7f4f78435..fbe27cb2c9d7 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -567,7 +567,8 @@ static int exact_lock(dev_t devt, void *data)
return 0;
}

-static void register_disk(struct device *parent, struct gendisk *disk)
+static void register_disk(struct device *parent, struct gendisk *disk,
+ const struct attribute_group **groups)
{
struct device *ddev = disk_to_dev(disk);
struct block_device *bdev;
@@ -582,6 +583,10 @@ static void register_disk(struct device *parent, struct gendisk *disk)
/* delay uevents, until we scanned partition table */
dev_set_uevent_suppress(ddev, 1);

+ if (groups) {
+ WARN_ON(ddev->groups);
+ ddev->groups = groups;
+ }
if (device_add(ddev))
return;
if (!sysfs_deprecated) {
@@ -647,13 +652,15 @@ static void register_disk(struct device *parent, struct gendisk *disk)
* __device_add_disk - add disk information to kernel list
* @parent: parent device for the disk
* @disk: per-device partitioning information
+ * @groups: Additional per-device sysfs groups
*
* This function registers the partitioning information in @disk
* with the kernel.
*
* FIXME: error handling
*/
-static void __device_add_disk(struct device *parent, struct gendisk *disk)
+static void __device_add_disk(struct device *parent, struct gendisk *disk,
+ const struct attribute_group **groups)
{
dev_t devt;
int retval;
@@ -696,7 +703,7 @@ static void __device_add_disk(struct device *parent, struct gendisk *disk)
blk_register_region(disk_devt(disk), disk->minors, NULL,
exact_match, exact_lock, disk);
}
- register_disk(parent, disk);
+ register_disk(parent, disk, groups);
}

void __device_get_disk(struct gendisk *disk)
@@ -711,9 +718,20 @@ void __device_get_disk(struct gendisk *disk)
blk_integrity_add(disk);
}

+void device_add_disk_with_groups(struct device *parent, struct gendisk *disk,
+ const struct attribute_group **groups)
+{
+ __device_add_disk(parent, disk, groups);
+
+ blk_register_queue(disk);
+
+ __device_get_disk(disk);
+}
+EXPORT_SYMBOL(device_add_disk_with_groups);
+
void device_add_disk(struct device *parent, struct gendisk *disk)
{
- __device_add_disk(parent, disk);
+ __device_add_disk(parent, disk, NULL);

blk_register_queue(disk);

@@ -723,7 +741,7 @@ EXPORT_SYMBOL(device_add_disk);

void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk)
{
- __device_add_disk(parent, disk);
+ __device_add_disk(parent, disk, NULL);
__device_get_disk(disk);
}
EXPORT_SYMBOL(device_add_disk_no_queue_reg);
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 6cb8a5789668..f41152979296 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -394,6 +394,9 @@ extern void part_round_stats(struct request_queue *q, int cpu, struct hd_struct

/* block/genhd.c */
extern void device_add_disk(struct device *parent, struct gendisk *disk);
+extern void device_add_disk_with_groups(struct device *parent,
+ struct gendisk *disk,
+ const struct attribute_group **groups);
static inline void add_disk(struct gendisk *disk)
{
device_add_disk(NULL, disk);
--
2.12.3