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-rw-r--r--include/linux/mm.h44
1 files changed, 44 insertions, 0 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h
index fda728e3c27d..91c08f6f0dc9 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -20,6 +20,7 @@
#include <linux/shrinker.h>
#include <linux/resource.h>
#include <linux/page_ext.h>
+#include <linux/err.h>
struct mempolicy;
struct anon_vma;
@@ -1214,6 +1215,49 @@ long get_user_pages_unlocked(struct task_struct *tsk, struct mm_struct *mm,
int write, int force, struct page **pages);
int get_user_pages_fast(unsigned long start, int nr_pages, int write,
struct page **pages);
+
+/* Container for pinned pfns / pages */
+struct frame_vector {
+ unsigned int nr_allocated; /* Number of frames we have space for */
+ unsigned int nr_frames; /* Number of frames stored in ptrs array */
+ bool got_ref; /* Did we pin pages by getting page ref? */
+ bool is_pfns; /* Does array contain pages or pfns? */
+ void *ptrs[0]; /* Array of pinned pfns / pages. Use
+ * pfns_vector_pages() or pfns_vector_pfns()
+ * for access */
+};
+
+struct frame_vector *frame_vector_create(unsigned int nr_frames);
+void frame_vector_destroy(struct frame_vector *vec);
+int get_vaddr_frames(unsigned long start, unsigned int nr_pfns,
+ bool write, bool force, struct frame_vector *vec);
+void put_vaddr_frames(struct frame_vector *vec);
+int frame_vector_to_pages(struct frame_vector *vec);
+void frame_vector_to_pfns(struct frame_vector *vec);
+
+static inline unsigned int frame_vector_count(struct frame_vector *vec)
+{
+ return vec->nr_frames;
+}
+
+static inline struct page **frame_vector_pages(struct frame_vector *vec)
+{
+ if (vec->is_pfns) {
+ int err = frame_vector_to_pages(vec);
+
+ if (err)
+ return ERR_PTR(err);
+ }
+ return (struct page **)(vec->ptrs);
+}
+
+static inline unsigned long *frame_vector_pfns(struct frame_vector *vec)
+{
+ if (!vec->is_pfns)
+ frame_vector_to_pfns(vec);
+ return (unsigned long *)(vec->ptrs);
+}
+
struct kvec;
int get_kernel_pages(const struct kvec *iov, int nr_pages, int write,
struct page **pages);