On 2020/7/16 下午7:23, Zhu Lingshan wrote:
This commit implements IRQ offloading helpers
Let's say "vq irq allocate/free helpers" here.
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.
vdpa_setup_irq() and vdpa_unsetup_irq(): supportive functions,
will call vhost_vdpa helpers.
Signed-off-by: Zhu Lingshan <lingshan....@intel.com>
Suggested-by: Jason Wang <jasow...@redhat.com>
---
drivers/vdpa/vdpa.c | 42 ++++++++++++++++++++++++++++++++++++++++++
include/linux/vdpa.h | 13 +++++++++++++
2 files changed, 55 insertions(+)
diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
index ff6562f..cce4d91 100644
--- a/drivers/vdpa/vdpa.c
+++ b/drivers/vdpa/vdpa.c
@@ -163,6 +163,48 @@ 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);
+
+ if (drv->setup_vq_irq)
+ drv->setup_vq_irq(vdev, qid, irq);
+}
+
+static void vdpa_unsetup_irq(struct vdpa_device *vdev, int qid)
+{
+ struct vdpa_driver *drv = drv_to_vdpa(vdev->dev.driver);
+
+ if (drv->unsetup_vq_irq)
+ drv->unsetup_vq_irq(vdev, qid);
Do you need to check the existence of drv before calling unset_vq_irq()?
And how can this synchronize with driver releasing and binding?
+}
+
+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)
Let's add comment as what has been done by other exported helpers.
+{
+ 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);
+
+ 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/include/linux/vdpa.h b/include/linux/vdpa.h
index 239db79..7d64d83 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -220,17 +220,30 @@ 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);
+/* request irq for a vq, setup irq offloading if its a vhost_vdpa vq */
Let's do the documentation in vdpa.c, and again, document the devres
implications or j_xxxust name it as vdpa_devm_xxx.
+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);
+/* free irq for a vq, unsetup irq offloading if its a vhost_vdpa vq */
+void vdpa_free_vq_irq(struct device *dev, struct vdpa_device *vdev, int irq,
+ int qid, void *dev_id);
+
/**
* 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 offloading for a vhost_vdpa vq.
+ * @unsetup_vq_irq: unsetup offloading for a vhost_vdpa vq.
Let's not limit the methods for a specific use case like irq offloading
here.
*/
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);
To be consistent with the exported helper, let's use
alloc_vq_irq/free_vq_irq
Thanks
};
#define vdpa_register_driver(drv) \
