[09/12] tcmu: simplify free_device

Commit Message

Mike Christie June 21, 2017, 9:33 p.m. UTC

The tcmu sync operation patch made device deletion synchronous, so the uio
close will always be done before the unregister, so this patch drops
the uneeded refcounting.

Signed-off-by: Mike Christie <[e-mail]>
---
 drivers/target/target_core_user.c | 43 ++++++++++-----------------------------
 1 file changed, 11 insertions(+), 32 deletions(-)

Patch

diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c
index 345476c..e86ac65 100644
--- a/drivers/target/target_core_user.c
+++ b/drivers/target/target_core_user.c
@@ -106,7 +106,6 @@  struct tcmu_nl_cmd {
 
 struct tcmu_dev {
 	struct list_head node;
-	struct kref kref;
 	struct se_device se_dev;
 
 	char *name;
@@ -1095,7 +1094,6 @@  static struct se_device *tcmu_alloc_device(struct se_hba *hba, const char *name)
 	udev = kzalloc(sizeof(struct tcmu_dev), GFP_KERNEL);
 	if (!udev)
 		return NULL;
-	kref_init(&udev->kref);
 
 	udev->name = kstrdup(name, GFP_KERNEL);
 	if (!udev->name) {
@@ -1275,24 +1273,6 @@  static int tcmu_open(struct uio_info *info, struct inode *inode)
 	return 0;
 }
 
-static void tcmu_dev_call_rcu(struct rcu_head *p)
-{
-	struct se_device *dev = container_of(p, struct se_device, rcu_head);
-	struct tcmu_dev *udev = TCMU_DEV(dev);
-
-	kfree(udev->uio_info.name);
-	kfree(udev->name);
-	kfree(udev);
-}
-
-static void tcmu_dev_kref_release(struct kref *kref)
-{
-	struct tcmu_dev *udev = container_of(kref, struct tcmu_dev, kref);
-	struct se_device *dev = &udev->se_dev;
-
-	call_rcu(&dev->rcu_head, tcmu_dev_call_rcu);
-}
-
 static int tcmu_release(struct uio_info *info, struct inode *inode)
 {
 	struct tcmu_dev *udev = container_of(info, struct tcmu_dev, uio_info);
@@ -1300,8 +1280,6 @@  static int tcmu_release(struct uio_info *info, struct inode *inode)
 	clear_bit(TCMU_DEV_BIT_OPEN, &udev->flags);
 
 	pr_debug("close\n");
-	/* release ref from configure */
-	kref_put(&udev->kref, tcmu_dev_kref_release);
 	return 0;
 }
 
@@ -1499,12 +1477,6 @@  static int tcmu_configure_device(struct se_device *dev)
 		dev->dev_attrib.emulate_write_cache = 0;
 	dev->dev_attrib.hw_queue_depth = 128;
 
-	/*
-	 * Get a ref incase userspace does a close on the uio device before
-	 * LIO has initiated tcmu_free_device.
-	 */
-	kref_get(&udev->kref);
-
 	ret = tcmu_netlink_event(udev, TCMU_CMD_ADDED_DEVICE, 0, NULL);
 	if (ret)
 		goto err_netlink;
@@ -1516,7 +1488,6 @@  static int tcmu_configure_device(struct se_device *dev)
 	return 0;
 
 err_netlink:
-	kref_put(&udev->kref, tcmu_dev_kref_release);
 	uio_unregister_device(&udev->uio_info);
 err_register:
 	vfree(udev->mb_addr);
@@ -1558,12 +1529,17 @@  static void tcmu_blocks_release(struct tcmu_dev *udev)
 	mutex_unlock(&udev->cmdr_lock);
 }
 
-static void tcmu_free_device(struct se_device *dev)
+static void tcmu_dev_call_rcu(struct rcu_head *p)
 {
+	struct se_device *dev = container_of(p, struct se_device, rcu_head);
 	struct tcmu_dev *udev = TCMU_DEV(dev);
 
-	/* release ref from init */
-	kref_put(&udev->kref, tcmu_dev_kref_release);
+	kfree(udev);
+}
+
+static void tcmu_free_device(struct se_device *dev)
+{
+	call_rcu(&dev->rcu_head, tcmu_dev_call_rcu);
 }
 
 static void tcmu_destroy_device(struct se_device *dev)
@@ -1597,6 +1573,9 @@  static void tcmu_destroy_device(struct se_device *dev)
 		tcmu_netlink_event(udev, TCMU_CMD_REMOVED_DEVICE, 0, NULL);
 
 		uio_unregister_device(&udev->uio_info);
+
+		kfree(udev->uio_info.name);
+		kfree(udev->name);
 	}
 }