From 070969f17d82e4220f5800ea63139e513cdb17fd Mon Sep 17 00:00:00 2001 From: David Sterba Date: Wed, 5 Jun 2024 02:28:30 +0200 Subject: btrfs: rework BTRFS_I as macro to preserve parameter const Currently BTRFS_I is a static inline function that takes a const inode and returns btrfs inode, dropping the 'const' qualifier. This can break assumptions of compiler though it seems there's no real case. To make the parameter and return type consistent regardint const we can use the container_of_const() that preserves it. However this would not check the parameter type. To fix that use the same _Generic construct but implement only the two expected types. Signed-off-by: David Sterba --- fs/btrfs/btrfs_inode.h | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'fs/btrfs') diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h index 90e72031c724..9a4b7c119318 100644 --- a/fs/btrfs/btrfs_inode.h +++ b/fs/btrfs/btrfs_inode.h @@ -350,10 +350,12 @@ static inline void btrfs_set_first_dir_index_to_log(struct btrfs_inode *inode, WRITE_ONCE(inode->first_dir_index_to_log, index); } -static inline struct btrfs_inode *BTRFS_I(const struct inode *inode) -{ - return container_of(inode, struct btrfs_inode, vfs_inode); -} +/* Type checked and const-preserving VFS inode -> btrfs inode. */ +#define BTRFS_I(_inode) \ + _Generic(_inode, \ + struct inode *: container_of(_inode, struct btrfs_inode, vfs_inode), \ + const struct inode *: (const struct btrfs_inode *)container_of( \ + _inode, const struct btrfs_inode, vfs_inode)) static inline unsigned long btrfs_inode_hash(u64 objectid, const struct btrfs_root *root) -- cgit v1.2.3-70-g09d2