3 files changed, 131 insertions, 44 deletions

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 37511d2b2caf..637c5bda2387 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -1775,14 +1775,43 @@ static const struct block_device_operations lo_fops = {
 /*
  * If max_loop is specified, create that many devices upfront.
  * This also becomes a hard limit. If max_loop is not specified,
+ * the default isn't a hard limit (as before commit 85c50197716c
+ * changed the default value from 0 for max_loop=0 reasons), just
  * create CONFIG_BLK_DEV_LOOP_MIN_COUNT loop devices at module
  * init time. Loop devices can be requested on-demand with the
  * /dev/loop-control interface, or be instantiated by accessing
  * a 'dead' device node.
  */
 static int max_loop = CONFIG_BLK_DEV_LOOP_MIN_COUNT;
-module_param(max_loop, int, 0444);
+
+#ifdef CONFIG_BLOCK_LEGACY_AUTOLOAD
+static bool max_loop_specified;
+
+static int max_loop_param_set_int(const char *val,
+				  const struct kernel_param *kp)
+{
+	int ret;
+
+	ret = param_set_int(val, kp);
+	if (ret < 0)
+		return ret;
+
+	max_loop_specified = true;
+	return 0;
+}
+
+static const struct kernel_param_ops max_loop_param_ops = {
+	.set = max_loop_param_set_int,
+	.get = param_get_int,
+};
+
+module_param_cb(max_loop, &max_loop_param_ops, &max_loop, 0444);
 MODULE_PARM_DESC(max_loop, "Maximum number of loop devices");
+#else
+module_param(max_loop, int, 0444);
+MODULE_PARM_DESC(max_loop, "Initial number of loop devices");
+#endif
+
 module_param(max_part, int, 0444);
 MODULE_PARM_DESC(max_part, "Maximum number of partitions per loop device");
 
@@ -2093,14 +2122,18 @@ static void loop_remove(struct loop_device *lo)
 	put_disk(lo->lo_disk);
 }
 
+#ifdef CONFIG_BLOCK_LEGACY_AUTOLOAD
 static void loop_probe(dev_t dev)
 {
 	int idx = MINOR(dev) >> part_shift;
 
-	if (max_loop && idx >= max_loop)
+	if (max_loop_specified && max_loop && idx >= max_loop)
 		return;
 	loop_add(idx);
 }
+#else
+#define loop_probe NULL
+#endif /* !CONFIG_BLOCK_LEGACY_AUTOLOAD */
 
 static int loop_control_remove(int idx)
 {
@@ -2281,6 +2314,9 @@ module_exit(loop_exit);
 static int __init max_loop_setup(char *str)
 {
 	max_loop = simple_strtol(str, NULL, 0);
+#ifdef CONFIG_BLOCK_LEGACY_AUTOLOAD
+	max_loop_specified = true;
+#endif
 	return 1;
 }
 
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index bd0e075a5d89..24afcc93ac01 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -3849,51 +3849,82 @@ static void wake_lock_waiters(struct rbd_device *rbd_dev, int result)
 	list_splice_tail_init(&rbd_dev->acquiring_list, &rbd_dev->running_list);
 }
 
-static int get_lock_owner_info(struct rbd_device *rbd_dev,
-			       struct ceph_locker **lockers, u32 *num_lockers)
+static bool locker_equal(const struct ceph_locker *lhs,
+			 const struct ceph_locker *rhs)
+{
+	return lhs->id.name.type == rhs->id.name.type &&
+	       lhs->id.name.num == rhs->id.name.num &&
+	       !strcmp(lhs->id.cookie, rhs->id.cookie) &&
+	       ceph_addr_equal_no_type(&lhs->info.addr, &rhs->info.addr);
+}
+
+static void free_locker(struct ceph_locker *locker)
+{
+	if (locker)
+		ceph_free_lockers(locker, 1);
+}
+
+static struct ceph_locker *get_lock_owner_info(struct rbd_device *rbd_dev)
 {
 	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
+	struct ceph_locker *lockers;
+	u32 num_lockers;
 	u8 lock_type;
 	char *lock_tag;
+	u64 handle;
 	int ret;
 
-	dout("%s rbd_dev %p\n", __func__, rbd_dev);
-
 	ret = ceph_cls_lock_info(osdc, &rbd_dev->header_oid,
 				 &rbd_dev->header_oloc, RBD_LOCK_NAME,
-				 &lock_type, &lock_tag, lockers, num_lockers);
-	if (ret)
-		return ret;
+				 &lock_type, &lock_tag, &lockers, &num_lockers);
+	if (ret) {
+		rbd_warn(rbd_dev, "failed to retrieve lockers: %d", ret);
+		return ERR_PTR(ret);
+	}
 
-	if (*num_lockers == 0) {
+	if (num_lockers == 0) {
 		dout("%s rbd_dev %p no lockers detected\n", __func__, rbd_dev);
+		lockers = NULL;
 		goto out;
 	}
 
 	if (strcmp(lock_tag, RBD_LOCK_TAG)) {
 		rbd_warn(rbd_dev, "locked by external mechanism, tag %s",
 			 lock_tag);
-		ret = -EBUSY;
-		goto out;
+		goto err_busy;
 	}
 
-	if (lock_type == CEPH_CLS_LOCK_SHARED) {
-		rbd_warn(rbd_dev, "shared lock type detected");
-		ret = -EBUSY;
-		goto out;
+	if (lock_type != CEPH_CLS_LOCK_EXCLUSIVE) {
+		rbd_warn(rbd_dev, "incompatible lock type detected");
+		goto err_busy;
 	}
 
-	if (strncmp((*lockers)[0].id.cookie, RBD_LOCK_COOKIE_PREFIX,
-		    strlen(RBD_LOCK_COOKIE_PREFIX))) {
+	WARN_ON(num_lockers != 1);
+	ret = sscanf(lockers[0].id.cookie, RBD_LOCK_COOKIE_PREFIX " %llu",
+		     &handle);
+	if (ret != 1) {
 		rbd_warn(rbd_dev, "locked by external mechanism, cookie %s",
-			 (*lockers)[0].id.cookie);
-		ret = -EBUSY;
-		goto out;
+			 lockers[0].id.cookie);
+		goto err_busy;
 	}
+	if (ceph_addr_is_blank(&lockers[0].info.addr)) {
+		rbd_warn(rbd_dev, "locker has a blank address");
+		goto err_busy;
+	}
+
+	dout("%s rbd_dev %p got locker %s%llu@%pISpc/%u handle %llu\n",
+	     __func__, rbd_dev, ENTITY_NAME(lockers[0].id.name),
+	     &lockers[0].info.addr.in_addr,
+	     le32_to_cpu(lockers[0].info.addr.nonce), handle);
 
 out:
 	kfree(lock_tag);
-	return ret;
+	return lockers;
+
+err_busy:
+	kfree(lock_tag);
+	ceph_free_lockers(lockers, num_lockers);
+	return ERR_PTR(-EBUSY);
 }
 
 static int find_watcher(struct rbd_device *rbd_dev,
@@ -3947,51 +3978,68 @@ out:
 static int rbd_try_lock(struct rbd_device *rbd_dev)
 {
 	struct ceph_client *client = rbd_dev->rbd_client->client;
-	struct ceph_locker *lockers;
-	u32 num_lockers;
+	struct ceph_locker *locker, *refreshed_locker;
 	int ret;
 
 	for (;;) {
+		locker = refreshed_locker = NULL;
+
 		ret = rbd_lock(rbd_dev);
 		if (ret != -EBUSY)
-			return ret;
+			goto out;
 
 		/* determine if the current lock holder is still alive */
-		ret = get_lock_owner_info(rbd_dev, &lockers, &num_lockers);
-		if (ret)
-			return ret;
-
-		if (num_lockers == 0)
+		locker = get_lock_owner_info(rbd_dev);
+		if (IS_ERR(locker)) {
+			ret = PTR_ERR(locker);
+			locker = NULL;
+			goto out;
+		}
+		if (!locker)
 			goto again;
 
-		ret = find_watcher(rbd_dev, lockers);
+		ret = find_watcher(rbd_dev, locker);
 		if (ret)
 			goto out; /* request lock or error */
 
+		refreshed_locker = get_lock_owner_info(rbd_dev);
+		if (IS_ERR(refreshed_locker)) {
+			ret = PTR_ERR(refreshed_locker);
+			refreshed_locker = NULL;
+			goto out;
+		}
+		if (!refreshed_locker ||
+		    !locker_equal(locker, refreshed_locker))
+			goto again;
+
 		rbd_warn(rbd_dev, "breaking header lock owned by %s%llu",
-			 ENTITY_NAME(lockers[0].id.name));
+			 ENTITY_NAME(locker->id.name));
 
 		ret = ceph_monc_blocklist_add(&client->monc,
-					      &lockers[0].info.addr);
+					      &locker->info.addr);
 		if (ret) {
-			rbd_warn(rbd_dev, "blocklist of %s%llu failed: %d",
-				 ENTITY_NAME(lockers[0].id.name), ret);
+			rbd_warn(rbd_dev, "failed to blocklist %s%llu: %d",
+				 ENTITY_NAME(locker->id.name), ret);
 			goto out;
 		}
 
 		ret = ceph_cls_break_lock(&client->osdc, &rbd_dev->header_oid,
 					  &rbd_dev->header_oloc, RBD_LOCK_NAME,
-					  lockers[0].id.cookie,
-					  &lockers[0].id.name);
-		if (ret && ret != -ENOENT)
+					  locker->id.cookie, &locker->id.name);
+		if (ret && ret != -ENOENT) {
+			rbd_warn(rbd_dev, "failed to break header lock: %d",
+				 ret);
 			goto out;
+		}
 
 again:
-		ceph_free_lockers(lockers, num_lockers);
+		free_locker(refreshed_locker);
+		free_locker(locker);
 	}
 
 out:
-	ceph_free_lockers(lockers, num_lockers);
+	free_locker(refreshed_locker);
+	free_locker(locker);
 	return ret;
 }
 
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index 1c823750c95a..21d2e71c5514 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -1847,7 +1847,8 @@ static int ublk_ctrl_start_dev(struct ublk_device *ub, struct io_uring_cmd *cmd)
 	if (ublksrv_pid <= 0)
 		return -EINVAL;
 
-	wait_for_completion_interruptible(&ub->completion);
+	if (wait_for_completion_interruptible(&ub->completion) != 0)
+		return -EINTR;
 
 	schedule_delayed_work(&ub->monitor_work, UBLK_DAEMON_MONITOR_PERIOD);
 
@@ -2125,8 +2126,8 @@ static int ublk_ctrl_del_dev(struct ublk_device **p_ub)
 	 * - the device number is freed already, we will not find this
 	 *   device via ublk_get_device_from_id()
 	 */
-	wait_event_interruptible(ublk_idr_wq, ublk_idr_freed(idx));
-
+	if (wait_event_interruptible(ublk_idr_wq, ublk_idr_freed(idx)))
+		return -EINTR;
 	return 0;
 }
 
@@ -2323,7 +2324,9 @@ static int ublk_ctrl_end_recovery(struct ublk_device *ub,
 	pr_devel("%s: Waiting for new ubq_daemons(nr: %d) are ready, dev id %d...\n",
 			__func__, ub->dev_info.nr_hw_queues, header->dev_id);
 	/* wait until new ubq_daemon sending all FETCH_REQ */
-	wait_for_completion_interruptible(&ub->completion);
+	if (wait_for_completion_interruptible(&ub->completion))
+		return -EINTR;
+
 	pr_devel("%s: All new ubq_daemons(nr: %d) are ready, dev id %d\n",
 			__func__, ub->dev_info.nr_hw_queues, header->dev_id);