Merge branch 'pci/host-vmd' into next

* pci/host-vmd:
  PCI: vmd: Fix suspend handlers defined-but-not-used warning
  PCI: vmd: Use SRCU as a local RCU to prevent delaying global RCU
  PCI: vmd: Remove unnecessary pci_set_drvdata()

2 files changed, 23 insertions, 9 deletions

diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index 117130968b80..898d2c48239c 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -288,7 +288,7 @@ config PCIE_ROCKCHIP
           4 slots.
 
 config VMD
-        depends on PCI_MSI && X86_64
+        depends on PCI_MSI && X86_64 && SRCU
         tristate "Intel Volume Management Device Driver"
         default N
         ---help---
diff --git a/drivers/pci/host/vmd.c b/drivers/pci/host/vmd.c
index 37e29b580be3..18ef1a93c10a 100644
--- a/drivers/pci/host/vmd.c
+++ b/drivers/pci/host/vmd.c
@@ -19,6 +19,7 @@
 #include <linux/module.h>
 #include <linux/msi.h>
 #include <linux/pci.h>
+#include <linux/srcu.h>
 #include <linux/rculist.h>
 #include <linux/rcupdate.h>
 
@@ -39,7 +40,6 @@ static DEFINE_RAW_SPINLOCK(list_lock);
 /**
  * struct vmd_irq - private data to map driver IRQ to the VMD shared vector
  * @node:       list item for parent traversal.
- * @rcu:        RCU callback item for freeing.
  * @irq:        back pointer to parent.
  * @enabled:    true if driver enabled IRQ
  * @virq:       the virtual IRQ value provided to the requesting driver.
@@ -49,7 +49,6 @@ static DEFINE_RAW_SPINLOCK(list_lock);
  */
 struct vmd_irq {
         struct list_head        node;
-        struct rcu_head         rcu;
         struct vmd_irq_list     *irq;
         bool                    enabled;
         unsigned int            virq;
@@ -58,11 +57,13 @@ struct vmd_irq {
 /**
  * struct vmd_irq_list - list of driver requested IRQs mapping to a VMD vector
  * @irq_list:   the list of irq's the VMD one demuxes to.
+ * @srcu:       SRCU struct for local synchronization.
  * @count:      number of child IRQs assigned to this vector; used to track
  *              sharing.
  */
 struct vmd_irq_list {
         struct list_head        irq_list;
+        struct srcu_struct      srcu;
         unsigned int            count;
 };
 
@@ -224,14 +225,14 @@ static void vmd_msi_free(struct irq_domain *domain,
         struct vmd_irq *vmdirq = irq_get_chip_data(virq);
         unsigned long flags;
 
-        synchronize_rcu();
+        synchronize_srcu(&vmdirq->irq->srcu);
 
         /* XXX: Potential optimization to rebalance */
         raw_spin_lock_irqsave(&list_lock, flags);
         vmdirq->irq->count--;
         raw_spin_unlock_irqrestore(&list_lock, flags);
 
-        kfree_rcu(vmdirq, rcu);
+        kfree(vmdirq);
 }
 
 static int vmd_msi_prepare(struct irq_domain *domain, struct device *dev,
@@ -646,11 +647,12 @@ static irqreturn_t vmd_irq(int irq, void *data)
 {
         struct vmd_irq_list *irqs = data;
         struct vmd_irq *vmdirq;
+        int idx;
 
-        rcu_read_lock();
+        idx = srcu_read_lock(&irqs->srcu);
         list_for_each_entry_rcu(vmdirq, &irqs->irq_list, node)
                 generic_handle_irq(vmdirq->virq);
-        rcu_read_unlock();
+        srcu_read_unlock(&irqs->srcu, idx);
 
         return IRQ_HANDLED;
 }
@@ -696,6 +698,10 @@ static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
                 return -ENOMEM;
 
         for (i = 0; i < vmd->msix_count; i++) {
+                err = init_srcu_struct(&vmd->irqs[i].srcu);
+                if (err)
+                        return err;
+
                 INIT_LIST_HEAD(&vmd->irqs[i].irq_list);
                 err = devm_request_irq(&dev->dev, pci_irq_vector(dev, i),
                                        vmd_irq, 0, "vmd", &vmd->irqs[i]);
@@ -714,12 +720,20 @@ static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
         return 0;
 }
 
+static void vmd_cleanup_srcu(struct vmd_dev *vmd)
+{
+        int i;
+
+        for (i = 0; i < vmd->msix_count; i++)
+                cleanup_srcu_struct(&vmd->irqs[i].srcu);
+}
+
 static void vmd_remove(struct pci_dev *dev)
 {
         struct vmd_dev *vmd = pci_get_drvdata(dev);
 
         vmd_detach_resources(vmd);
-        pci_set_drvdata(dev, NULL);
+        vmd_cleanup_srcu(vmd);
         sysfs_remove_link(&vmd->dev->dev.kobj, "domain");
         pci_stop_root_bus(vmd->bus);
         pci_remove_root_bus(vmd->bus);
@@ -727,7 +741,7 @@ static void vmd_remove(struct pci_dev *dev)
         irq_domain_remove(vmd->irq_domain);
 }
 
-#ifdef CONFIG_PM
+#ifdef CONFIG_PM_SLEEP
 static int vmd_suspend(struct device *dev)
 {
         struct pci_dev *pdev = to_pci_dev(dev);