IB/core: Fix mismatch between locked and pinned pages

Commit bc3e53f682d9 ("mm: distinguish between mlocked and pinned
pages") introduced a separate counter for pinned pages and used it in
the IB stack. However, in ib_umem_get() the pinned counter is
incremented, but ib_umem_release() wrongly decrements the locked
counter. Fix this.

Signed-off-by: Yishai Hadas <[e-mail]>
Reviewed-by: Christoph Lameter <[e-mail]>
Cc: <[e-mail]>
Signed-off-by: Roland Dreier <[e-mail]>

drivers/infiniband/core/umem.c

···
 	} else
 		down_write(&mm->mmap_sem);
 
-	current->mm->locked_vm -= diff;
+	current->mm->pinned_vm -= diff;
 	up_write(&mm->mmap_sem);
 	mmput(mm);
 	kfree(umem);