On Wed, Nov 22, 2023 at 2:27 PM Amir Goldstein <amir73il@xxxxxxxxx> wrote:
>
> Similar to sb_write_started() for use by other sb freeze levels.
>
> Unlike the boolean sb_write_started(), this helper returns a tristate
> to distiguish the cases of lockdep disabled or unknown lock state.
>
> This is needed for fanotify "pre content" events.
>
> Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
> ---
> include/linux/fs.h | 15 ++++++++++++++-
> 1 file changed, 14 insertions(+), 1 deletion(-)
>
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index 98b7a7a8c42e..e8aa48797bf4 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -1645,9 +1645,22 @@ static inline bool __sb_start_write_trylock(struct super_block *sb, int level)
> #define __sb_writers_release(sb, lev) \
> percpu_rwsem_release(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
>
> +/**
> + * __sb_write_started - check if sb freeze level is held
> + * @sb: the super we write to
Missing Kerneldoc of arg:
+ * @level: the freeze level
> + *
> + * > 0 sb freeze level is held
> + * 0 sb freeze level is not held
> + * < 0 !CONFIG_LOCKDEP/LOCK_STATE_UNKNOWN
> + */
> +static inline int __sb_write_started(const struct super_block *sb, int level)
> +{
> + return lockdep_is_held_type(sb->s_writers.rw_sem + level - 1, 1);
> +}
> +
> static inline bool sb_write_started(const struct super_block *sb)
> {
> - return lockdep_is_held_type(sb->s_writers.rw_sem + SB_FREEZE_WRITE - 1, 1);
> + return __sb_write_started(sb, SB_FREEZE_WRITE);
> }
>
> /**
> --
> 2.34.1
>
