1133 static int xol_add_vma(struct mm_struct *mm, struct xol_area *area)  in xol_add_vma()  argument
1141 	if (!area->vaddr) {  in xol_add_vma()
1143 		area->vaddr = get_unmapped_area(NULL, TASK_SIZE - PAGE_SIZE,  in xol_add_vma()
1145 		if (area->vaddr & ~PAGE_MASK) {  in xol_add_vma()
1146 			ret = area->vaddr;  in xol_add_vma()
1151 	ret = install_special_mapping(mm, area->vaddr, PAGE_SIZE,  in xol_add_vma()
1152 				VM_EXEC|VM_MAYEXEC|VM_DONTCOPY|VM_IO, &area->page);  in xol_add_vma()
1157 	mm->uprobes_state.xol_area = area;  in xol_add_vma()
1168 	struct xol_area *area;  in __create_xol_area()  local
1170 	area = kmalloc(sizeof(*area), GFP_KERNEL);  in __create_xol_area()
1171 	if (unlikely(!area))  in __create_xol_area()
1174 	area->bitmap = kzalloc(BITS_TO_LONGS(UINSNS_PER_PAGE) * sizeof(long), GFP_KERNEL);  in __create_xol_area()
1175 	if (!area->bitmap)  in __create_xol_area()
1178 	area->page = alloc_page(GFP_HIGHUSER);  in __create_xol_area()
1179 	if (!area->page)  in __create_xol_area()
1182 	area->vaddr = vaddr;  in __create_xol_area()
1183 	init_waitqueue_head(&area->wq);  in __create_xol_area()
1185 	set_bit(0, area->bitmap);  in __create_xol_area()
1186 	atomic_set(&area->slot_count, 1);  in __create_xol_area()
1187 	copy_to_page(area->page, 0, &insn, UPROBE_SWBP_INSN_SIZE);  in __create_xol_area()
1189 	if (!xol_add_vma(mm, area))  in __create_xol_area()
1190 		return area;  in __create_xol_area()
1192 	__free_page(area->page);  in __create_xol_area()
1194 	kfree(area->bitmap);  in __create_xol_area()
1196 	kfree(area);  in __create_xol_area()
1210 	struct xol_area *area;  in get_xol_area()  local
1215 	area = mm->uprobes_state.xol_area;  in get_xol_area()
1217 	return area;  in get_xol_area()
1225 	struct xol_area *area = mm->uprobes_state.xol_area;  in uprobe_clear_state()  local
1227 	if (!area)  in uprobe_clear_state()
1230 	put_page(area->page);  in uprobe_clear_state()
1231 	kfree(area->bitmap);  in uprobe_clear_state()
1232 	kfree(area);  in uprobe_clear_state()
1259 static unsigned long xol_take_insn_slot(struct xol_area *area)  in xol_take_insn_slot()  argument
1265 		slot_nr = find_first_zero_bit(area->bitmap, UINSNS_PER_PAGE);  in xol_take_insn_slot()
1267 			if (!test_and_set_bit(slot_nr, area->bitmap))  in xol_take_insn_slot()
1273 		wait_event(area->wq, (atomic_read(&area->slot_count) < UINSNS_PER_PAGE));  in xol_take_insn_slot()
1276 	slot_addr = area->vaddr + (slot_nr * UPROBE_XOL_SLOT_BYTES);  in xol_take_insn_slot()
1277 	atomic_inc(&area->slot_count);  in xol_take_insn_slot()
1288 	struct xol_area *area;  in xol_get_insn_slot()  local
1291 	area = get_xol_area();  in xol_get_insn_slot()
1292 	if (!area)  in xol_get_insn_slot()
1295 	xol_vaddr = xol_take_insn_slot(area);  in xol_get_insn_slot()
1299 	arch_uprobe_copy_ixol(area->page, xol_vaddr,  in xol_get_insn_slot()
1312 	struct xol_area *area;  in xol_free_insn_slot()  local
1323 	area = tsk->mm->uprobes_state.xol_area;  in xol_free_insn_slot()
1324 	vma_end = area->vaddr + PAGE_SIZE;  in xol_free_insn_slot()
1325 	if (area->vaddr <= slot_addr && slot_addr < vma_end) {  in xol_free_insn_slot()
1329 		offset = slot_addr - area->vaddr;  in xol_free_insn_slot()
1334 		clear_bit(slot_nr, area->bitmap);  in xol_free_insn_slot()
1335 		atomic_dec(&area->slot_count);  in xol_free_insn_slot()
1336 		if (waitqueue_active(&area->wq))  in xol_free_insn_slot()
1337 			wake_up(&area->wq);  in xol_free_insn_slot()
1473 	struct xol_area *area;  in uprobe_copy_process()  local
1487 	area = mm->uprobes_state.xol_area;  in uprobe_copy_process()
1488 	if (!area)  in uprobe_copy_process()
1494 	t->utask->dup_xol_addr = area->vaddr;  in uprobe_copy_process()
1507 	struct xol_area *area;  in get_trampoline_vaddr()  local
1510 	area = current->mm->uprobes_state.xol_area;  in get_trampoline_vaddr()
1512 	if (area)  in get_trampoline_vaddr()
1513 		trampoline_vaddr = area->vaddr;  in get_trampoline_vaddr()