1 files changed, 31 insertions, 0 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h
index c2307a2d275d..62bd89414897 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2373,6 +2373,37 @@ int follow_pte(struct vm_area_struct *vma, unsigned long address,
 int generic_access_phys(struct vm_area_struct *vma, unsigned long addr,
 			void *buf, int len, int write);
 
+struct follow_pfnmap_args {
+	/**
+	 * Inputs:
+	 * @vma: Pointer to @vm_area_struct struct
+	 * @address: the virtual address to walk
+	 */
+	struct vm_area_struct *vma;
+	unsigned long address;
+	/**
+	 * Internals:
+	 *
+	 * The caller shouldn't touch any of these.
+	 */
+	spinlock_t *lock;
+	pte_t *ptep;
+	/**
+	 * Outputs:
+	 *
+	 * @pfn: the PFN of the address
+	 * @pgprot: the pgprot_t of the mapping
+	 * @writable: whether the mapping is writable
+	 * @special: whether the mapping is a special mapping (real PFN maps)
+	 */
+	unsigned long pfn;
+	pgprot_t pgprot;
+	bool writable;
+	bool special;
+};
+int follow_pfnmap_start(struct follow_pfnmap_args *args);
+void follow_pfnmap_end(struct follow_pfnmap_args *args);
+
 extern void truncate_pagecache(struct inode *inode, loff_t new);
 extern void truncate_setsize(struct inode *inode, loff_t newsize);
 void pagecache_isize_extended(struct inode *inode, loff_t from, loff_t to);