From: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
Date: Sat, 16 Jul 2022 16:33:43 -0700
> The previous patch added flock_translate_cmd() in flock syscall.
> The test does not depend on struct fd and the cheapest, so we can
> put it at the top and defer fdget() after that.
>
> Also, we can remove the unlock variable and use type instead.
> As a bonus, we fix this checkpatch error.
>
> CHECK: spaces preferred around that '|' (ctx:VxV)
> #45: FILE: fs/locks.c:2099:
> + if (type != F_UNLCK && !(f.file->f_mode & (FMODE_READ|FMODE_WRITE)))
> ^
>
> Finally, we can move the can_sleep part just before we use it.
>
> Signed-off-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
> ---
> fs/locks.c | 34 +++++++++++++++-------------------
> 1 file changed, 15 insertions(+), 19 deletions(-)
>
> diff --git a/fs/locks.c b/fs/locks.c
> index b134eaefd7d6..97581678c4d4 100644
> --- a/fs/locks.c
> +++ b/fs/locks.c
> @@ -2083,19 +2083,20 @@ EXPORT_SYMBOL(locks_lock_inode_wait);
> */
> SYSCALL_DEFINE2(flock, unsigned int, fd, unsigned int, cmd)
> {
> - int can_sleep, error, unlock, type;
> - struct fd f = fdget(fd);
> + int can_sleep, error, type;
> struct file_lock fl;
> + struct fd f;
> +
> + type = flock_translate_cmd(cmd & ~LOCK_NB);
> + if (type < 0)
> + return type;
Sorry, we have to check (cmd & LOCK_MAND) first.
Will fix in v3.
>
> error = -EBADF;
> + f = fdget(fd);
> if (!f.file)
> - goto out;
> -
> - can_sleep = !(cmd & LOCK_NB);
> - cmd &= ~LOCK_NB;
> - unlock = (cmd == LOCK_UN);
> + return error;
>
> - if (!unlock && !(f.file->f_mode & (FMODE_READ|FMODE_WRITE)))
> + if (type != F_UNLCK && !(f.file->f_mode & (FMODE_READ | FMODE_WRITE)))
> goto out_putf;
>
> /*
> @@ -2112,31 +2113,26 @@ SYSCALL_DEFINE2(flock, unsigned int, fd, unsigned int, cmd)
> goto out_putf;
> }
>
> - type = flock_translate_cmd(cmd);
> - if (type < 0) {
> - error = type;
> - goto out_putf;
> - }
> -
> flock_make_lock(f.file, &fl, type);
>
> - if (can_sleep)
> - fl.fl_flags |= FL_SLEEP;
> -
> error = security_file_lock(f.file, fl.fl_type);
> if (error)
> goto out_putf;
>
> + can_sleep = !(cmd & LOCK_NB);
> + if (can_sleep)
> + fl.fl_flags |= FL_SLEEP;
> +
> if (f.file->f_op->flock)
> error = f.file->f_op->flock(f.file,
> - (can_sleep) ? F_SETLKW : F_SETLK,
> + (can_sleep) ? F_SETLKW : F_SETLK,
> &fl);
> else
> error = locks_lock_file_wait(f.file, &fl);
>
> out_putf:
> fdput(f);
> - out:
> +
> return error;
> }
>
> --
> 2.30.2
