+#define LDLM_MAX_GROWN_EXTENT (32 * 1024 * 1024 - 1)
+
+/* fixup the ldlm_extent after expanding */
+static void ldlm_extent_internal_policy_fixup(struct ldlm_lock *req,
+ struct ldlm_extent *new_ex,
+ int conflicting)
+{
+ ldlm_mode_t req_mode = req->l_req_mode;
+ __u64 req_start = req->l_req_extent.start;
+ __u64 req_end = req->l_req_extent.end;
+ __u64 req_align, mask;
+
+ if (conflicting > 32 && (req_mode == LCK_PW || req_mode == LCK_CW)) {
+ if (req_end < req_start + LDLM_MAX_GROWN_EXTENT)
+ new_ex->end = min(req_start + LDLM_MAX_GROWN_EXTENT,
+ new_ex->end);
+ }
+
+ if (new_ex->start == 0 && new_ex->end == OBD_OBJECT_EOF) {
+ EXIT;
+ return;
+ }
+
+ /* we need to ensure that the lock extent is properly aligned to what
+ * the client requested. We align it to the lowest-common denominator
+ * of the clients requested lock start and end alignment. */
+ mask = 0x1000ULL;
+ req_align = (req_end + 1) | req_start;
+ if (req_align != 0) {
+ while ((req_align & mask) == 0)
+ mask <<= 1;
+ }
+ mask -= 1;
+ /* We can only shrink the lock, not grow it.
+ * This should never cause lock to be smaller than requested,
+ * since requested lock was already aligned on these boundaries. */
+ new_ex->start = ((new_ex->start - 1) | mask) + 1;
+ new_ex->end = ((new_ex->end + 1) & ~mask) - 1;
+ LASSERTF(new_ex->start <= req_start,
+ "mask "LPX64" grant start "LPU64" req start "LPU64"\n",
+ mask, new_ex->start, req_start);
+ LASSERTF(new_ex->end >= req_end,
+ "mask "LPX64" grant end "LPU64" req end "LPU64"\n",
+ mask, new_ex->end, req_end);
+}
+
+/* The purpose of this function is to return:
+ * - the maximum extent
+ * - containing the requested extent
+ * - and not overlapping existing conflicting extents outside the requested one
+ *
+ * Use interval tree to expand the lock extent for granted lock.
+ */
+static void ldlm_extent_internal_policy_granted(struct ldlm_lock *req,
+ struct ldlm_extent *new_ex)
+{
+ struct ldlm_resource *res = req->l_resource;
+ ldlm_mode_t req_mode = req->l_req_mode;
+ __u64 req_start = req->l_req_extent.start;
+ __u64 req_end = req->l_req_extent.end;
+ struct ldlm_interval_tree *tree;
+ struct interval_node_extent limiter = { new_ex->start, new_ex->end };
+ int conflicting = 0;
+ int idx;
+ ENTRY;
+
+ lockmode_verify(req_mode);
+
+ /* using interval tree to handle the ldlm extent granted locks */
+ for (idx = 0; idx < LCK_MODE_NUM; idx++) {
+ struct interval_node_extent ext = { req_start, req_end };
+
+ tree = &res->lr_itree[idx];
+ if (lockmode_compat(tree->lit_mode, req_mode))
+ continue;
+
+ conflicting += tree->lit_size;
+ if (conflicting > 4)
+ limiter.start = req_start;
+
+ if (interval_is_overlapped(tree->lit_root, &ext))
+ printk("req_mode = %d, tree->lit_mode = %d, tree->lit_size = %d\n",
+ req_mode, tree->lit_mode, tree->lit_size);
+ interval_expand(tree->lit_root, &ext, &limiter);
+ limiter.start = max(limiter.start, ext.start);
+ limiter.end = min(limiter.end, ext.end);
+ if (limiter.start == req_start && limiter.end == req_end)
+ break;
+ }
+
+ new_ex->start = limiter.start;
+ new_ex->end = limiter.end;
+ LASSERT(new_ex->start <= req_start);
+ LASSERT(new_ex->end >= req_end);
+
+ ldlm_extent_internal_policy_fixup(req, new_ex, conflicting);
+ EXIT;
+}
+