mm: merge populate and nopage into fault (fixes nonlinear)

[mirror_ubuntu-zesty-kernel.git] / include / linux / mm.h

diff --git a/include/linux/mm.h b/include/linux/mm.h
index ca9536a348c85a025c08144443f7307019c85aa5..f28a1b3e63a91ffe988b11f749e4ca1120f2ea9b 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -173,6 +173,7 @@ extern unsigned int kobjsize(const void *objp);
                                         * In this case, do_no_page must
                                         * return with the page locked.
                                         */
+#define VM_CAN_NONLINEAR 0x10000000    /* Has ->fault & does nonlinear pages */
 
 #ifndef VM_STACK_DEFAULT_FLAGS         /* arch can override this */
 #define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS
@@ -196,6 +197,25 @@ extern unsigned int kobjsize(const void *objp);
  */
 extern pgprot_t protection_map[16];
 
+#define FAULT_FLAG_WRITE       0x01
+#define FAULT_FLAG_NONLINEAR   0x02
+
+/*
+ * fault_data is filled in the the pagefault handler and passed to the
+ * vma's ->fault function. That function is responsible for filling in
+ * 'type', which is the type of fault if a page is returned, or the type
+ * of error if NULL is returned.
+ *
+ * pgoff should be used in favour of address, if possible. If pgoff is
+ * used, one may set VM_CAN_NONLINEAR in the vma->vm_flags to get
+ * nonlinear mapping support.
+ */
+struct fault_data {
+       unsigned long address;
+       pgoff_t pgoff;
+       unsigned int flags;
+       int type;
+};
 
 /*
  * These are the virtual MM functions - opening of an area, closing and
@@ -205,9 +225,15 @@ extern pgprot_t protection_map[16];
 struct vm_operations_struct {
        void (*open)(struct vm_area_struct * area);
        void (*close)(struct vm_area_struct * area);
-       struct page * (*nopage)(struct vm_area_struct * area, unsigned long address, int *type);
-       unsigned long (*nopfn)(struct vm_area_struct * area, unsigned long address);
-       int (*populate)(struct vm_area_struct * area, unsigned long address, unsigned long len, pgprot_t prot, unsigned long pgoff, int nonblock);
+       struct page *(*fault)(struct vm_area_struct *vma,
+                       struct fault_data *fdata);
+       struct page *(*nopage)(struct vm_area_struct *area,
+                       unsigned long address, int *type);
+       unsigned long (*nopfn)(struct vm_area_struct *area,
+                       unsigned long address);
+       int (*populate)(struct vm_area_struct *area, unsigned long address,
+                       unsigned long len, pgprot_t prot, unsigned long pgoff,
+                       int nonblock);
 
        /* notification that a previously read-only page is about to become
         * writable, if an error is returned it will cause a SIGBUS */
@@ -661,7 +687,6 @@ static inline int page_mapped(struct page *page)
  */
 #define NOPAGE_SIGBUS  (NULL)
 #define NOPAGE_OOM     ((struct page *) (-1))
-#define NOPAGE_REFAULT ((struct page *) (-2))  /* Return to userspace, rerun */
 
 /*
  * Error return values for the *_nopfn functions
@@ -1110,9 +1135,11 @@ extern void truncate_inode_pages_range(struct address_space *,
                                       loff_t lstart, loff_t lend);
 
 /* generic vm_area_ops exported for stackable file systems */
-extern struct page *filemap_nopage(struct vm_area_struct *, unsigned long, int *);
-extern int filemap_populate(struct vm_area_struct *, unsigned long,
-               unsigned long, pgprot_t, unsigned long, int);
+extern struct page *filemap_fault(struct vm_area_struct *, struct fault_data *);
+extern struct page * __deprecated_for_modules
+filemap_nopage(struct vm_area_struct *, unsigned long, int *);
+extern int __deprecated_for_modules filemap_populate(struct vm_area_struct *,
+               unsigned long, unsigned long, pgprot_t, unsigned long, int);
 
 /* mm/page-writeback.c */
 int write_one_page(struct page *page, int wait);