- cfs_list_t *tmp;
- struct ldlm_lock *lock;
- ldlm_mode_t req_mode = req->l_req_mode;
- __u64 req_bits = req->l_policy_data.l_inodebits.bits;
- int compat = 1;
- ENTRY;
-
- LASSERT(req_bits); /* There is no sense in lock with no bits set,
- I think. Also such a lock would be compatible
- with any other bit lock */
-
- cfs_list_for_each(tmp, queue) {
- cfs_list_t *mode_tail;
-
- lock = cfs_list_entry(tmp, struct ldlm_lock, l_res_link);
-
- if (req == lock)
- RETURN(compat);
-
- /* last lock in mode group */
- LASSERT(lock->l_sl_mode.prev != NULL);
- mode_tail = &cfs_list_entry(lock->l_sl_mode.prev,
- struct ldlm_lock,
- l_sl_mode)->l_res_link;
-
- /* locks are compatible, bits don't matter */
- if (lockmode_compat(lock->l_req_mode, req_mode)) {
- /* jump to last lock in mode group */
- tmp = mode_tail;
- continue;
- }
-
- for (;;) {
- cfs_list_t *head;
-
- /* last lock in policy group */
- tmp = &cfs_list_entry(lock->l_sl_policy.prev,
- struct ldlm_lock,
- l_sl_policy)->l_res_link;
-
- /* locks with bits overlapped are conflicting locks */
- if (lock->l_policy_data.l_inodebits.bits & req_bits) {
- /* COS lock from the same client is
- not conflicting */
- if (lock->l_req_mode == LCK_COS &&
- lock->l_client_cookie == req->l_client_cookie)
- goto not_conflicting;
- /* conflicting policy */
- if (!work_list)
- RETURN(0);
-
- compat = 0;
-
- /* add locks of the policy group to
- * @work_list as blocking locks for
- * @req */
+ struct list_head *tmp;
+ struct ldlm_lock *lock;
+ __u64 req_bits = req->l_policy_data.l_inodebits.bits;
+ int compat = 1;
+ ENTRY;
+
+ /* There is no sense in lock with no bits set, I think.
+ * Also, such a lock would be compatible with any other bit lock */
+ LASSERT(req_bits != 0);
+
+ list_for_each(tmp, queue) {
+ struct list_head *mode_tail;
+
+ lock = list_entry(tmp, struct ldlm_lock, l_res_link);
+
+ /* We stop walking the queue if we hit ourselves so we don't
+ * take conflicting locks enqueued after us into account,
+ * or we'd wait forever. */
+ if (req == lock)
+ RETURN(compat);
+
+ /* last lock in mode group */
+ LASSERT(lock->l_sl_mode.prev != NULL);
+ mode_tail = &list_entry(lock->l_sl_mode.prev,
+ struct ldlm_lock,
+ l_sl_mode)->l_res_link;
+
+ /* if reqest lock is not COS_INCOMPAT and COS is disabled,
+ * they are compatible, IOW this request is from a local
+ * transaction on a DNE system. */
+ if (lock->l_req_mode == LCK_COS && !ldlm_is_cos_incompat(req) &&
+ !ldlm_is_cos_enabled(req)) {
+ /* jump to last lock in mode group */
+ tmp = mode_tail;
+ continue;
+ }
+
+ /* locks' mode are compatible, bits don't matter */
+ if (lockmode_compat(lock->l_req_mode, req->l_req_mode)) {
+ /* jump to last lock in mode group */
+ tmp = mode_tail;
+ continue;
+ }
+
+ for (;;) {
+ struct list_head *head;
+
+ /* Advance loop cursor to last lock in policy group. */
+ tmp = &list_entry(lock->l_sl_policy.prev,
+ struct ldlm_lock,
+ l_sl_policy)->l_res_link;
+
+ /* Locks with overlapping bits conflict. */
+ if (lock->l_policy_data.l_inodebits.bits & req_bits) {
+ /* COS lock mode has a special compatibility
+ * requirement: it is only compatible with
+ * locks from the same client. */
+ if (lock->l_req_mode == LCK_COS &&
+ !ldlm_is_cos_incompat(req) &&
+ ldlm_is_cos_enabled(req) &&
+ lock->l_client_cookie == req->l_client_cookie)
+ goto not_conflicting;
+ /* Found a conflicting policy group. */
+ if (!work_list)
+ RETURN(0);
+
+ compat = 0;
+
+ /* Add locks of the policy group to @work_list
+ * as blocking locks for @req */