locks: give lm_break a return value

Christoph suggests:

   "Add a return value to lm_break so that the lock manager can tell the
    core code "you can delete this lease right now".  That gets rid of
    the games with the timeout which require all kinds of race avoidance
    code in the users."

Do that here and have the nfsd lease break routine use it when it detects
that there was a race between setting up the lease and it being broken.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Jeff Layton
2014-09-01 15:06:54 -04:00
parent 03d12ddf84
commit 4d01b7f5e7
3 changed files with 23 additions and 13 deletions

View File

@@ -872,7 +872,7 @@ struct lock_manager_operations {
void (*lm_put_owner)(struct file_lock *);
void (*lm_notify)(struct file_lock *); /* unblock callback */
int (*lm_grant)(struct file_lock *, int);
void (*lm_break)(struct file_lock *);
bool (*lm_break)(struct file_lock *);
int (*lm_change)(struct file_lock **, int, struct list_head *);
void (*lm_setup)(struct file_lock *, void **);
};