diff options
| -rw-r--r-- | block/blk.h | 13 | ||||
| -rw-r--r-- | block/genhd.c | 4 |
2 files changed, 8 insertions, 9 deletions
diff --git a/block/blk.h b/block/blk.h index 73bd3b1c6938..8c3f557dd898 100644 --- a/block/blk.h +++ b/block/blk.h @@ -378,19 +378,18 @@ int bdev_resize_partition(struct block_device *bdev, int partno, int disk_expand_part_tbl(struct gendisk *disk, int target); int hd_ref_init(struct hd_struct *part); -static inline void hd_struct_get(struct hd_struct *part) -{ - percpu_ref_get(&part->ref); -} - +/* no need to get/put refcount of part0 */ static inline int hd_struct_try_get(struct hd_struct *part) { - return percpu_ref_tryget_live(&part->ref); + if (part->partno) + return percpu_ref_tryget_live(&part->ref); + return 1; } static inline void hd_struct_put(struct hd_struct *part) { - percpu_ref_put(&part->ref); + if (part->partno) + percpu_ref_put(&part->ref); } static inline void hd_free_part(struct hd_struct *part) diff --git a/block/genhd.c b/block/genhd.c index 1a51a9ad1035..afdb2c3e5b22 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -345,7 +345,8 @@ static inline int sector_in_part(struct hd_struct *part, sector_t sector) * * CONTEXT: * RCU read locked. The returned partition pointer is always valid - * because its refcount is grabbed. + * because its refcount is grabbed except for part0, which lifetime + * is same with the disk. * * RETURNS: * Found partition on success, part0 is returned if no partition matches @@ -378,7 +379,6 @@ struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector) return part; } } - hd_struct_get(&disk->part0); return &disk->part0; } |