On 2020/7/12 下午10:49, Zhu Lingshan wrote:
This commit implements IRQ offloading helpers in vDPA core by
introducing two couple of functions:
vdpa_alloc_vq_irq() and vdpa_free_vq_irq(): request irq and free
irq, will setup irq offloading if irq_bypass is enabled.
vdpa_setup_irq() and vdpa_unsetup_irq(): supportive functions,
will call vhost_vdpa helpers.
Signed-off-by: Zhu Lingshan <lingshan.zhu@xxxxxxxxx>
This patch should go before patch 3.
---
drivers/vdpa/vdpa.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
drivers/vhost/Kconfig | 1 +
drivers/vhost/vdpa.c | 2 ++
include/linux/vdpa.h | 11 +++++++++++
4 files changed, 60 insertions(+)
diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
index ff6562f..d8eba01 100644
--- a/drivers/vdpa/vdpa.c
+++ b/drivers/vdpa/vdpa.c
@@ -163,6 +163,52 @@ void vdpa_unregister_driver(struct vdpa_driver *drv)
}
EXPORT_SYMBOL_GPL(vdpa_unregister_driver);
+static void vdpa_setup_irq(struct vdpa_device *vdev, int qid, int irq)
+{
+ struct vdpa_driver *drv = drv_to_vdpa(vdev->dev.driver);
+
+#ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
Let's don't do the check here. It's the responsibility of driver to
decide what it should do.
+ if (drv->setup_vq_irq)
+ drv->setup_vq_irq(vdev, qid, irq);
+#endif
+}
+
+static void vdpa_unsetup_irq(struct vdpa_device *vdev, int qid)
+{
+ struct vdpa_driver *drv = drv_to_vdpa(vdev->dev.driver);
+
+#ifdef CONFIG_HAVE_KVM_IRQ_BYPASS
+ if (drv->unsetup_vq_irq)
+ drv->unsetup_vq_irq(vdev, qid);
+#endif
+}
+
+int vdpa_alloc_vq_irq(struct device *dev, struct vdpa_device *vdev,
+ unsigned int irq, irq_handler_t handler,
+ unsigned long irqflags, const char *devname, void *dev_id,
+ int qid)
+{
+ int ret;
+
+ ret = devm_request_irq(dev, irq, handler, irqflags, devname, dev_id);
+ if (ret)
+ dev_err(dev, "Failed to request irq for vq %d\n", qid);
+ else
+ vdpa_setup_irq(vdev, qid, irq);
I'd like to squash the vdpa_setup_irq logic here.
+
+ return ret;
+
+}
+EXPORT_SYMBOL_GPL(vdpa_alloc_vq_irq);
+
+void vdpa_free_vq_irq(struct device *dev, struct vdpa_device *vdev, int irq,
+ int qid, void *dev_id)
+{
+ devm_free_irq(dev, irq, dev_id);
+ vdpa_unsetup_irq(vdev, qid);
+}
+EXPORT_SYMBOL_GPL(vdpa_free_vq_irq);
+
static int vdpa_init(void)
{
return bus_register(&vdpa_bus);
diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
Let squash the vhost patch into patch 3.
index d3688c6..587fbae 100644
--- a/drivers/vhost/Kconfig
+++ b/drivers/vhost/Kconfig
@@ -65,6 +65,7 @@ config VHOST_VDPA
tristate "Vhost driver for vDPA-based backend"
depends on EVENTFD
select VHOST
+ select IRQ_BYPASS_MANAGER
depends on VDPA
help
This kernel module can be loaded in host kernel to accelerate
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 92683e4..6e25158 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -1020,6 +1020,8 @@ static void vhost_vdpa_remove(struct vdpa_device *vdpa)
},
.probe = vhost_vdpa_probe,
.remove = vhost_vdpa_remove,
+ .setup_vq_irq = vhost_vdpa_setup_vq_irq,
+ .unsetup_vq_irq = vhost_vdpa_unsetup_vq_irq,
};
static int __init vhost_vdpa_init(void)
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index 239db79..9f9b245 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -220,17 +220,28 @@ struct vdpa_device *__vdpa_alloc_device(struct device *parent,
int vdpa_register_device(struct vdpa_device *vdev);
void vdpa_unregister_device(struct vdpa_device *vdev);
+int vdpa_alloc_vq_irq(struct device *dev, struct vdpa_device *vdev,
+ unsigned int irq, irq_handler_t handler,
+ unsigned long irqflags, const char *devname, void *dev_id,
+ int qid);
+void vdpa_free_vq_irq(struct device *dev, struct vdpa_device *vdev, int irq,
+ int qid, void *dev_id);
You need to document the devres implications of those two helpers.
+
/**
* vdpa_driver - operations for a vDPA driver
* @driver: underlying device driver
* @probe: the function to call when a device is found. Returns 0 or -errno.
* @remove: the function to call when a device is removed.
+ * @setup_vq_irq: setup irq bypass for a vhost_vdpa vq.
+ * @unsetup_vq_irq: unsetup irq bypass for a vhost_vdpa vq.
Though irq bypass is used by vhost-vdpa, it's not necessarily to be true
in the future. So it's better not to mention irqbypass in the doc here.
Thanks
*/
struct vdpa_driver {
struct device_driver driver;
int (*probe)(struct vdpa_device *vdev);
void (*remove)(struct vdpa_device *vdev);
+ void (*setup_vq_irq)(struct vdpa_device *vdev, int qid, int irq);
+ void (*unsetup_vq_irq)(struct vdpa_device *vdev, int qid);
};
#define vdpa_register_driver(drv) \
