mmap.c: deinline a few functions

__vma_link_file and expand_downwards functions are not small, yeat they
are marked inline. They probably had one callsite sometime in the past,
but now they have more. In order to prevent similar thing, I also
deinlined expand_upwards, despite it having only pne callsite. Nowadays
gcc auto-inlines such static functions anyway. In find_extend_vma, I
removed one extra level of indirection.

Patch is deliberately generated with -U $BIGNUM to make
it easier to see that functions are big.

Result:

# size */*/mmap.o */vmlinux
text data bss dec hex filename
9514 188 16 9718 25f6 0.org/mm/mmap.o
9237 188 16 9441 24e1 deinline/mm/mmap.o
6124402 858996 389480 7372878 70804e 0.org/vmlinux
6124113 858996 389480 7372589 707f2d deinline/vmlinux

Signed-off-by: Denys Vlasenko <[e-mail]>
Cc: Hugh Dickins <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

mm/mmap.c

···
 	rb_insert_color(&vma->vm_rb, &mm->mm_rb);
 }
 
-static inline void __vma_link_file(struct vm_area_struct *vma)
+static void __vma_link_file(struct vm_area_struct *vma)
 {
 	struct file * file;
 
···
  * vma is the last one with address > vma->vm_end.  Have to extend vma.
  */
 #ifndef CONFIG_IA64
-static inline
+static
 #endif
 int expand_upwards(struct vm_area_struct *vma, unsigned long address)
 {
···
 /*
  * vma is the first one with address < vma->vm_start.  Have to extend vma.
  */
-static inline int expand_downwards(struct vm_area_struct *vma,
+static int expand_downwards(struct vm_area_struct *vma,
 				   unsigned long address)
 {
 	int error;
···
 	vma = find_vma_prev(mm, addr, &prev);
 	if (vma && (vma->vm_start <= addr))
 		return vma;
-	if (!prev || expand_stack(prev, addr))
+	if (expand_stack(prev, addr))
 		return NULL;
 	if (prev->vm_flags & VM_LOCKED) {
 		if (mlock_vma_pages_range(prev, addr, prev->vm_end) < 0)