[PATCH] virtual => physical page mapping cache

Implement a "mapping change" notification for virtual lookup caches, and
make the futex code use that to keep the futex page pinning consistent
across copy-on-write events in the VM space.

1 files changed, 26 insertions, 0 deletions

diff --git a/include/linux/vcache.h b/include/linux/vcache.h
new file mode 100644
index 000000000000..d5756643332c
--- /dev/null
+++ b/include/linux/vcache.h
@@ -0,0 +1,26 @@
+/*
+ * virtual => physical mapping cache support.
+ */
+#ifndef _LINUX_VCACHE_H
+#define _LINUX_VCACHE_H
+
+typedef struct vcache_s {
+	unsigned long address;
+	struct mm_struct *mm;
+	struct list_head hash_entry;
+	void (*callback)(struct vcache_s *data, struct page *new_page);
+} vcache_t;
+
+extern spinlock_t vcache_lock;
+
+extern void __attach_vcache(vcache_t *vcache,
+		unsigned long address,
+		struct mm_struct *mm,
+		void (*callback)(struct vcache_s *data, struct page *new_page));
+
+extern void detach_vcache(vcache_t *vcache);
+
+extern void invalidate_vcache(unsigned long address, struct mm_struct *mm,
+				struct page *new_page);
+
+#endif