222 _shift_data_left_pages(struct page **pages, size_t pgto_base,  in _shift_data_left_pages()  argument
229 	BUG_ON(pgfrom_base <= pgto_base);  in _shift_data_left_pages()
231 	pgto = pages + (pgto_base >> PAGE_SHIFT);  in _shift_data_left_pages()
234 	pgto_base &= ~PAGE_MASK;  in _shift_data_left_pages()
238 		if (pgto_base >= PAGE_SIZE) {  in _shift_data_left_pages()
239 			pgto_base = 0;  in _shift_data_left_pages()
248 		if (copy > (PAGE_SIZE - pgto_base))  in _shift_data_left_pages()
249 			copy = PAGE_SIZE - pgto_base;  in _shift_data_left_pages()
256 			memcpy(vto + pgto_base, vfrom + pgfrom_base, copy);  in _shift_data_left_pages()
259 			memmove(vto + pgto_base, vto + pgfrom_base, copy);  in _shift_data_left_pages()
263 		pgto_base += copy;  in _shift_data_left_pages()
304 _shift_data_right_pages(struct page **pages, size_t pgto_base,  in _shift_data_right_pages()  argument
311 	BUG_ON(pgto_base <= pgfrom_base);  in _shift_data_right_pages()
313 	pgto_base += len;  in _shift_data_right_pages()
316 	pgto = pages + (pgto_base >> PAGE_SHIFT);  in _shift_data_right_pages()
319 	pgto_base &= ~PAGE_MASK;  in _shift_data_right_pages()
324 		if (pgto_base == 0) {  in _shift_data_right_pages()
325 			pgto_base = PAGE_SIZE;  in _shift_data_right_pages()
334 		if (copy > pgto_base)  in _shift_data_right_pages()
335 			copy = pgto_base;  in _shift_data_right_pages()
338 		pgto_base -= copy;  in _shift_data_right_pages()
344 			memcpy(vto + pgto_base, vfrom + pgfrom_base, copy);  in _shift_data_right_pages()
347 			memmove(vto + pgto_base, vto + pgfrom_base, copy);  in _shift_data_right_pages()