diff options
Diffstat (limited to 'include/linux/kernfs.h')
| -rw-r--r-- | include/linux/kernfs.h | 20 |
1 files changed, 14 insertions, 6 deletions
diff --git a/include/linux/kernfs.h b/include/linux/kernfs.h index 38267cc9420c..dded2e5a9f42 100644 --- a/include/linux/kernfs.h +++ b/include/linux/kernfs.h @@ -141,8 +141,8 @@ struct kernfs_node { void *priv; /* - * 64bit unique ID. Lower 32bits carry the inode number and lower - * generation. + * 64bit unique ID. On 64bit ino setups, id is the ino. On 32bit, + * the low 32bits are ino and upper generation. */ u64 id; @@ -177,8 +177,8 @@ struct kernfs_root { /* private fields, do not use outside kernfs proper */ struct idr ino_idr; - u32 last_ino; - u32 next_generation; + u32 last_id_lowbits; + u32 id_highbits; struct kernfs_syscall_ops *syscall_ops; /* list of kernfs_super_info of this root, protected by kernfs_mutex */ @@ -284,12 +284,20 @@ static inline enum kernfs_node_type kernfs_type(struct kernfs_node *kn) static inline ino_t kernfs_id_ino(u64 id) { - return (u32)id; + /* id is ino if ino_t is 64bit; otherwise, low 32bits */ + if (sizeof(ino_t) >= sizeof(u64)) + return id; + else + return (u32)id; } static inline u32 kernfs_id_gen(u64 id) { - return id >> 32; + /* gen is fixed at 1 if ino_t is 64bit; otherwise, high 32bits */ + if (sizeof(ino_t) >= sizeof(u64)) + return 1; + else + return id >> 32; } static inline ino_t kernfs_ino(struct kernfs_node *kn) |