217 _shift_data_left_pages(struct page **pages, size_t pgto_base,  in _shift_data_left_pages()  argument
224 	BUG_ON(pgfrom_base <= pgto_base);  in _shift_data_left_pages()
229 	pgto = pages + (pgto_base >> PAGE_SHIFT);  in _shift_data_left_pages()
232 	pgto_base &= ~PAGE_MASK;  in _shift_data_left_pages()
236 		if (pgto_base >= PAGE_SIZE) {  in _shift_data_left_pages()
237 			pgto_base = 0;  in _shift_data_left_pages()
246 		if (copy > (PAGE_SIZE - pgto_base))  in _shift_data_left_pages()
247 			copy = PAGE_SIZE - pgto_base;  in _shift_data_left_pages()
254 			memcpy(vto + pgto_base, vfrom + pgfrom_base, copy);  in _shift_data_left_pages()
257 			memmove(vto + pgto_base, vto + pgfrom_base, copy);  in _shift_data_left_pages()
261 		pgto_base += copy;  in _shift_data_left_pages()
282 _shift_data_right_pages(struct page **pages, size_t pgto_base,  in _shift_data_right_pages()  argument
289 	BUG_ON(pgto_base <= pgfrom_base);  in _shift_data_right_pages()
294 	pgto_base += len;  in _shift_data_right_pages()
297 	pgto = pages + (pgto_base >> PAGE_SHIFT);  in _shift_data_right_pages()
300 	pgto_base &= ~PAGE_MASK;  in _shift_data_right_pages()
305 		if (pgto_base == 0) {  in _shift_data_right_pages()
306 			pgto_base = PAGE_SIZE;  in _shift_data_right_pages()
315 		if (copy > pgto_base)  in _shift_data_right_pages()
316 			copy = pgto_base;  in _shift_data_right_pages()
319 		pgto_base -= copy;  in _shift_data_right_pages()
325 			memcpy(vto + pgto_base, vfrom + pgfrom_base, copy);  in _shift_data_right_pages()
328 			memmove(vto + pgto_base, vto + pgfrom_base, copy);  in _shift_data_right_pages()