[PATCH 7/9] bdi: remove bdi_register_owner

From: Christoph Hellwig
Date: Mon May 04 2020 - 08:57:24 EST


Split out a new bdi_set_owner helper to set the owner, and move the policy
for creating the bdi name back into genhd.c, where it belongs.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Jan Kara <jack@xxxxxxx>
Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Bart Van Assche <bvanassche@xxxxxxx>
---
block/genhd.c | 8 +++++---
include/linux/backing-dev.h | 2 +-
mm/backing-dev.c | 12 ++----------
3 files changed, 8 insertions(+), 14 deletions(-)

diff --git a/block/genhd.c b/block/genhd.c
index c05d509877fa7..27511b3d164dd 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -840,13 +840,15 @@ static void __device_add_disk(struct device *parent, struct gendisk *disk,
disk->flags |= GENHD_FL_SUPPRESS_PARTITION_INFO;
disk->flags |= GENHD_FL_NO_PART_SCAN;
} else {
+ struct backing_dev_info *bdi = disk->queue->backing_dev_info;
+ struct device *dev = disk_to_dev(disk);
int ret;

/* Register BDI before referencing it from bdev */
- disk_to_dev(disk)->devt = devt;
- ret = bdi_register_owner(disk->queue->backing_dev_info,
- disk_to_dev(disk));
+ dev->devt = devt;
+ ret = bdi_register(bdi, "%u:%u", MAJOR(devt), MINOR(devt));
WARN_ON(ret);
+ bdi_set_owner(bdi, dev);
blk_register_region(disk_devt(disk), disk->minors, NULL,
exact_match, exact_lock, disk);
}
diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h
index c9ad5c3b7b4b2..4098ed6ba6b43 100644
--- a/include/linux/backing-dev.h
+++ b/include/linux/backing-dev.h
@@ -33,7 +33,7 @@ int bdi_register(struct backing_dev_info *bdi, const char *fmt, ...);
__printf(2, 0)
int bdi_register_va(struct backing_dev_info *bdi, const char *fmt,
va_list args);
-int bdi_register_owner(struct backing_dev_info *bdi, struct device *owner);
+void bdi_set_owner(struct backing_dev_info *bdi, struct device *owner);
void bdi_unregister(struct backing_dev_info *bdi);

struct backing_dev_info *bdi_alloc_node(gfp_t gfp_mask, int node_id);
diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index eb6b51e49d11f..bb993f99d4244 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -977,20 +977,12 @@ int bdi_register(struct backing_dev_info *bdi, const char *fmt, ...)
}
EXPORT_SYMBOL(bdi_register);

-int bdi_register_owner(struct backing_dev_info *bdi, struct device *owner)
+void bdi_set_owner(struct backing_dev_info *bdi, struct device *owner)
{
- int rc;
-
- rc = bdi_register(bdi, "%u:%u", MAJOR(owner->devt), MINOR(owner->devt));
- if (rc)
- return rc;
- /* Leaking owner reference... */
- WARN_ON(bdi->owner);
+ WARN_ON_ONCE(bdi->owner);
bdi->owner = owner;
get_device(owner);
- return 0;
}
-EXPORT_SYMBOL(bdi_register_owner);

/*
* Remove bdi from bdi_list, and ensure that it is no longer visible
--
2.26.2