Code that allocates locks using locks_alloc_lock() will free it
using locks_free_lock(), and will benefit from the BUG_ON()
consistency checks therein.
However some code (nfsd and lockd) allocate a lock embedded in
some other data structure, and so free the lock themselves after
calling locks_release_private(). This path does not benefit from
the consistency checks.
To help catch future errors, move the BUG_ON() checks to
locks_release_private() - which locks_free_lock() already calls.
This ensures that all users for locks will find out if the lock
isn't detached properly before being free.
Signed-off-by: NeilBrown <neilb@xxxxxxxx>
---
fs/locks.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/fs/locks.c b/fs/locks.c
index 71d0c6c2aac5..456a3782c6ca 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -352,6 +352,12 @@ EXPORT_SYMBOL_GPL(locks_alloc_lock);
void locks_release_private(struct file_lock *fl)
{
+ BUG_ON(waitqueue_active(&fl->fl_wait));
+ BUG_ON(!list_empty(&fl->fl_list));
+ BUG_ON(!list_empty(&fl->fl_blocked_requests));
+ BUG_ON(!list_empty(&fl->fl_blocked_member));
+ BUG_ON(!hlist_unhashed(&fl->fl_link));
+
if (fl->fl_ops) {
if (fl->fl_ops->fl_release_private)
fl->fl_ops->fl_release_private(fl);
@@ -371,12 +377,6 @@ EXPORT_SYMBOL_GPL(locks_release_private);
/* Free a lock which is not in use. */
void locks_free_lock(struct file_lock *fl)
{
- BUG_ON(waitqueue_active(&fl->fl_wait));
- BUG_ON(!list_empty(&fl->fl_list));
- BUG_ON(!list_empty(&fl->fl_blocked_requests));
- BUG_ON(!list_empty(&fl->fl_blocked_member));
- BUG_ON(!hlist_unhashed(&fl->fl_link));
-
locks_release_private(fl);
kmem_cache_free(filelock_cache, fl);
}
--
2.14.0.rc0.dirty
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