uprobes: Cleanup !CONFIG_UPROBES decls, unexport xol_area

[platform/adaptation/renesas_rcar/renesas_kernel.git] / kernel / events / uprobes.c

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 445962a..51a7f53 100644 (file)
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -86,6 +86,25 @@ struct return_instance {
 };
 
 /*
+ * On a breakpoint hit, thread contests for a slot.  It frees the
+ * slot after singlestep. Currently a fixed number of slots are
+ * allocated.
+ */
+struct xol_area {
+       wait_queue_head_t       wq;             /* if all slots are busy */
+       atomic_t                slot_count;     /* number of in-use slots */
+       unsigned long           *bitmap;        /* 0 = free slot */
+       struct page             *page;
+
+       /*
+        * We keep the vma's vm_start rather than a pointer to the vma
+        * itself.  The probed process or a naughty kernel module could make
+        * the vma go away, and we must handle that reasonably gracefully.
+        */
+       unsigned long           vaddr;          /* Page(s) of instruction slots */
+};
+
+/*
  * valid_vma: Verify if the specified vma is an executable vma
  * Relax restrictions while unregistering: vm_flags might have
  * changed after breakpoint was inserted.