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Diffstat (limited to 'fs/btrfs/volumes.h')
| -rw-r--r-- | fs/btrfs/volumes.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index 3930ee01d696..d44cb9d22d63 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -580,6 +580,17 @@ static inline unsigned long btrfs_chunk_item_size(int num_stripes) sizeof(struct btrfs_stripe) * (num_stripes - 1); } +/* + * Do the type safe converstion from stripe_nr to offset inside the chunk. + * + * @stripe_nr is u32, with left shift it can overflow u32 for chunks larger + * than 4G. This does the proper type cast to avoid overflow. + */ +static inline u64 btrfs_stripe_nr_to_offset(u32 stripe_nr) +{ + return (u64)stripe_nr << BTRFS_STRIPE_LEN_SHIFT; +} + void btrfs_get_bioc(struct btrfs_io_context *bioc); void btrfs_put_bioc(struct btrfs_io_context *bioc); int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op, |