ovl: narrow locking in ovl_whiteout()

ovl_whiteout() relies on the workdir i_rwsem to provide exclusive access
to ofs->whiteout which it manipulates.  Rather than depending on this,
add a new mutex, "whiteout_lock" to explicitly provide the required
locking.  Use guard(mutex) for this so that we can return without
needing to explicitly unlock.

Then take the lock on workdir only when needed - to lookup the temp name
and to do the whiteout or link.

Signed-off-by: NeilBrown <[email protected]>
Link: https://lore.kernel.org/[email protected]
Reviewed-by: Amir Goldstein <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

0 files changed, 0 insertions, 0 deletions