sys/kern/kern_lockf.c

851  * Return non-zero if locks 'x' and 'y' overlap.
994 	struct lockf_entry *overlap;
997 	LIST_FOREACH(overlap, &state->ls_active, lf_link) {
1002 		if (overlap->lf_start > lock->lf_end)
1004 		if (!lf_blocks(lock, overlap))
1012 		error = lf_add_edge(lock, overlap);
1032 	LIST_FOREACH(overlap, &state->ls_pending, lf_link) {
1033 		if (!lf_blocks(lock, overlap))
1040 		error = lf_add_edge(lock, overlap);
1062 	struct lockf_entry *overlap;
1065 	LIST_FOREACH(overlap, &state->ls_pending, lf_link) {
1066 		if (!lf_blocks(lock, overlap))
1074 		error = lf_add_edge(overlap, lock);
1215 	struct lockf_entry *overlap, *lf;
1228 		 * any locks that overlap and are owned by ourselves.
1230 		overlap = LIST_FIRST(&state->ls_active);
1232 			ovcase = lf_findoverlap(&overlap, lock, SELF);
1236 				printf("lf_setlock: overlap %d", ovcase);
1237 				lf_print("", overlap);
1242 			 *	0) no overlap
1243 			 *	1) overlap == lock
1244 			 *	2) overlap contains lock
1245 			 *	3) lock contains overlap
1246 			 *	4) overlap starts before lock
1247 			 *	5) overlap ends after lock
1250 			case 0: /* no overlap */
1253 			case 1: /* overlap == lock */
1260 				LIST_REMOVE(overlap, lf_link);
1261 				lf_update_dependancies(state, overlap, TRUE,
1263 				lf_free_lock(overlap);
1266 			case 2: /* overlap contains lock */
1270 				lf_split(state, overlap, lock, &granted);
1273 			case 3: /* lock contains overlap */
1275 				 * Delete the overlap and advance to
1278 				lf = LIST_NEXT(overlap, lf_link);
1279 				LIST_REMOVE(overlap, lf_link);
1280 				lf_update_dependancies(state, overlap, TRUE,
1282 				lf_free_lock(overlap);
1283 				overlap = lf;
1286 			case 4: /* overlap starts before lock */
1288 				 * Just update the overlap end and
1291 				lf_set_end(state, overlap, lock->lf_start - 1,
1293 				overlap = LIST_NEXT(overlap, lf_link);
1296 			case 5: /* overlap ends after lock */
1298 				 * Change the start of overlap and
1301 				lf_set_start(state, overlap, lock->lf_end + 1,
1547  * Generally, find the lock (or an overlap to that lock)
1553 	struct lockf_entry *overlap;
1555 	overlap = LIST_FIRST(&state->ls_active);
1557 	if (overlap == NOLOCKF)
1660 	struct lockf_entry *overlap;
1662 	LIST_FOREACH(overlap, &state->ls_active, lf_link) {
1667 		if (overlap->lf_start > lock->lf_end)
1669 		if (!lf_blocks(lock, overlap))
1671 		return (overlap);
1678  * any) and return a classification of that overlap.
1681  *	*overlap	The place in the lock list to start looking
1688  *	0) no overlap
1689  *	1) overlap == lock
1690  *	2) overlap contains lock
1691  *	3) lock contains overlap
1692  *	4) overlap starts before lock
1693  *	5) overlap ends after lock
1695  * If there is an overlapping lock, '*overlap' is set to point at the
1702 lf_findoverlap(struct lockf_entry **overlap, struct lockf_entry *lock, int type)
1708 	if ((*overlap) == NOLOCKF) {
1713 		lf_print("lf_findoverlap: looking for overlap in", lock);
1718 	while (*overlap) {
1719 		lf = *overlap;
1724 			*overlap = LIST_NEXT(lf, lf_link);
1732 		 * OK, check for overlap
1735 		 *	0) no overlap
1736 		 *	1) overlap == lock
1737 		 *	2) overlap contains lock
1738 		 *	3) lock contains overlap
1739 		 *	4) overlap starts before lock
1740 		 *	5) overlap ends after lock
1746 				printf("no overlap\n");
1748 			*overlap = LIST_NEXT(lf, lf_link);
1755 				printf("overlap == lock\n");
1764 				printf("overlap contains lock\n");
1773 				printf("lock contains overlap\n");
1782 				printf("overlap starts before lock\n");
1791 				printf("overlap ends after lock\n");