1 files changed, 47 insertions, 18 deletions

diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 50b04ae5c394..5dab531c8654 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -1041,7 +1041,7 @@ static struct pcie_link_state *pcie_aspm_get_link(struct pci_dev *pdev)
 	return bridge->link_state;
 }
 
-static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem)
+static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool locked)
 {
 	struct pcie_link_state *link = pcie_aspm_get_link(pdev);
 
@@ -1060,7 +1060,7 @@ static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem)
 		return -EPERM;
 	}
 
-	if (sem)
+	if (!locked)
 		down_read(&pci_bus_sem);
 	mutex_lock(&aspm_lock);
 	if (state & PCIE_LINK_STATE_L0S)
@@ -1082,7 +1082,7 @@ static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem)
 		link->clkpm_disable = 1;
 	pcie_set_clkpm(link, policy_to_clkpm_state(link));
 	mutex_unlock(&aspm_lock);
-	if (sem)
+	if (!locked)
 		up_read(&pci_bus_sem);
 
 	return 0;
@@ -1090,7 +1090,9 @@ static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem)
 
 int pci_disable_link_state_locked(struct pci_dev *pdev, int state)
 {
-	return __pci_disable_link_state(pdev, state, false);
+	lockdep_assert_held_read(&pci_bus_sem);
+
+	return __pci_disable_link_state(pdev, state, true);
 }
 EXPORT_SYMBOL(pci_disable_link_state_locked);
 
@@ -1105,21 +1107,11 @@ EXPORT_SYMBOL(pci_disable_link_state_locked);
  */
 int pci_disable_link_state(struct pci_dev *pdev, int state)
 {
-	return __pci_disable_link_state(pdev, state, true);
+	return __pci_disable_link_state(pdev, state, false);
 }
 EXPORT_SYMBOL(pci_disable_link_state);
 
-/**
- * pci_enable_link_state - Clear and set the default device link state so that
- * the link may be allowed to enter the specified states. Note that if the
- * BIOS didn't grant ASPM control to the OS, this does nothing because we can't
- * touch the LNKCTL register. Also note that this does not enable states
- * disabled by pci_disable_link_state(). Return 0 or a negative errno.
- *
- * @pdev: PCI device
- * @state: Mask of ASPM link states to enable
- */
-int pci_enable_link_state(struct pci_dev *pdev, int state)
+static int __pci_enable_link_state(struct pci_dev *pdev, int state, bool locked)
 {
 	struct pcie_link_state *link = pcie_aspm_get_link(pdev);
 
@@ -1136,7 +1128,8 @@ int pci_enable_link_state(struct pci_dev *pdev, int state)
 		return -EPERM;
 	}
 
-	down_read(&pci_bus_sem);
+	if (!locked)
+		down_read(&pci_bus_sem);
 	mutex_lock(&aspm_lock);
 	link->aspm_default = 0;
 	if (state & PCIE_LINK_STATE_L0S)
@@ -1157,12 +1150,48 @@ int pci_enable_link_state(struct pci_dev *pdev, int state)
 	link->clkpm_default = (state & PCIE_LINK_STATE_CLKPM) ? 1 : 0;
 	pcie_set_clkpm(link, policy_to_clkpm_state(link));
 	mutex_unlock(&aspm_lock);
-	up_read(&pci_bus_sem);
+	if (!locked)
+		up_read(&pci_bus_sem);
 
 	return 0;
 }
+
+/**
+ * pci_enable_link_state - Clear and set the default device link state so that
+ * the link may be allowed to enter the specified states. Note that if the
+ * BIOS didn't grant ASPM control to the OS, this does nothing because we can't
+ * touch the LNKCTL register. Also note that this does not enable states
+ * disabled by pci_disable_link_state(). Return 0 or a negative errno.
+ *
+ * @pdev: PCI device
+ * @state: Mask of ASPM link states to enable
+ */
+int pci_enable_link_state(struct pci_dev *pdev, int state)
+{
+	return __pci_enable_link_state(pdev, state, false);
+}
 EXPORT_SYMBOL(pci_enable_link_state);
 
+/**
+ * pci_enable_link_state_locked - Clear and set the default device link state
+ * so that the link may be allowed to enter the specified states. Note that if
+ * the BIOS didn't grant ASPM control to the OS, this does nothing because we
+ * can't touch the LNKCTL register. Also note that this does not enable states
+ * disabled by pci_disable_link_state(). Return 0 or a negative errno.
+ *
+ * @pdev: PCI device
+ * @state: Mask of ASPM link states to enable
+ *
+ * Context: Caller holds pci_bus_sem read lock.
+ */
+int pci_enable_link_state_locked(struct pci_dev *pdev, int state)
+{
+	lockdep_assert_held_read(&pci_bus_sem);
+
+	return __pci_enable_link_state(pdev, state, true);
+}
+EXPORT_SYMBOL(pci_enable_link_state_locked);
+
 static int pcie_aspm_set_policy(const char *val,
 				const struct kernel_param *kp)
 {