Make __fdget() et.al. return struct fd directly. New helpers: BORROWED_FD(file) and CLONED_FD(file), for borrowed and cloned file references resp. NOTE: this might need tuning; in particular, inline on __fget_light() is there to keep the code generation same as before - we probably want to keep it inlined in fdget() et.al. (especially so in fdget_pos()), but that needs profiling. Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx> --- fs/file.c | 26 +++++++++++++------------- include/linux/file.h | 33 +++++++++++---------------------- 2 files changed, 24 insertions(+), 35 deletions(-) diff --git a/fs/file.c b/fs/file.c index 8076aef9c210..f78e114a03cc 100644 --- a/fs/file.c +++ b/fs/file.c @@ -1128,7 +1128,7 @@ EXPORT_SYMBOL(task_lookup_next_fdget_rcu); * The fput_needed flag returned by fget_light should be passed to the * corresponding fput_light. */ -static unsigned long __fget_light(unsigned int fd, fmode_t mask) +static inline struct fd __fget_light(unsigned int fd, fmode_t mask) { struct files_struct *files = current->files; struct file *file; @@ -1145,22 +1145,22 @@ static unsigned long __fget_light(unsigned int fd, fmode_t mask) if (likely(atomic_read_acquire(&files->count) == 1)) { file = files_lookup_fd_raw(files, fd); if (!file || unlikely(file->f_mode & mask)) - return 0; - return (unsigned long)file; + return EMPTY_FD; + return BORROWED_FD(file); } else { file = __fget_files(files, fd, mask); if (!file) - return 0; - return FDPUT_FPUT | (unsigned long)file; + return EMPTY_FD; + return CLONED_FD(file); } } -unsigned long __fdget(unsigned int fd) +struct fd fdget(unsigned int fd) { return __fget_light(fd, FMODE_PATH); } -EXPORT_SYMBOL(__fdget); +EXPORT_SYMBOL(fdget); -unsigned long __fdget_raw(unsigned int fd) +struct fd fdget_raw(unsigned int fd) { return __fget_light(fd, 0); } @@ -1181,16 +1181,16 @@ static inline bool file_needs_f_pos_lock(struct file *file) (file_count(file) > 1 || file->f_op->iterate_shared); } -unsigned long __fdget_pos(unsigned int fd) +struct fd fdget_pos(unsigned int fd) { - unsigned long v = __fdget(fd); - struct file *file = (struct file *)(v & ~3); + struct fd f = fdget(fd); + struct file *file = fd_file(f); if (file && file_needs_f_pos_lock(file)) { - v |= FDPUT_POS_UNLOCK; + f.word |= FDPUT_POS_UNLOCK; mutex_lock(&file->f_pos_lock); } - return v; + return f; } void __f_unlock_pos(struct file *f) diff --git a/include/linux/file.h b/include/linux/file.h index 39eb10a1bbfc..7bc6e24e86ce 100644 --- a/include/linux/file.h +++ b/include/linux/file.h @@ -53,6 +53,14 @@ static inline bool fd_empty(struct fd f) } #define EMPTY_FD (struct fd){0} +static inline struct fd BORROWED_FD(struct file *f) +{ + return (struct fd){(unsigned long)f}; +} +static inline struct fd CLONED_FD(struct file *f) +{ + return (struct fd){(unsigned long)f | FDPUT_FPUT}; +} static inline void fdput(struct fd fd) { @@ -63,30 +71,11 @@ static inline void fdput(struct fd fd) extern struct file *fget(unsigned int fd); extern struct file *fget_raw(unsigned int fd); extern struct file *fget_task(struct task_struct *task, unsigned int fd); -extern unsigned long __fdget(unsigned int fd); -extern unsigned long __fdget_raw(unsigned int fd); -extern unsigned long __fdget_pos(unsigned int fd); extern void __f_unlock_pos(struct file *); -static inline struct fd __to_fd(unsigned long v) -{ - return (struct fd){v}; -} - -static inline struct fd fdget(unsigned int fd) -{ - return __to_fd(__fdget(fd)); -} - -static inline struct fd fdget_raw(unsigned int fd) -{ - return __to_fd(__fdget_raw(fd)); -} - -static inline struct fd fdget_pos(int fd) -{ - return __to_fd(__fdget_pos(fd)); -} +struct fd fdget(unsigned int fd); +struct fd fdget_raw(unsigned int fd); +struct fd fdget_pos(unsigned int fd); static inline void fdput_pos(struct fd f) { -- 2.39.2