[PATCH v11 28/40] virtio_pci: introduce helper to get/set queue reset

Xuan Zhuo
2022-06-29T07:00:02Z

Introduce new helpers to implement queue reset and get queue reset
status.

https://github.com/oasis-tcs/virtio-spec/issues/124
https://github.com/oasis-tcs/virtio-spec/issues/139

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
---
drivers/virtio/virtio_pci_modern_dev.c | 35 ++++++++++++++++++++++++++
include/linux/virtio_pci_modern.h | 2 ++
2 files changed, 37 insertions(+)

diff --git a/drivers/virtio/virtio_pci_modern_dev.c b/drivers/virtio/virtio_pci_modern_dev.c
index fa2a9445bb18..07415654247c 100644
--- a/drivers/virtio/virtio_pci_modern_dev.c
+++ b/drivers/virtio/virtio_pci_modern_dev.c
@@ -3,6 +3,7 @@
#include <linux/virtio_pci_modern.h>
#include <linux/module.h>
#include <linux/pci.h>
+#include <linux/delay.h>

/*
* vp_modern_map_capability - map a part of virtio pci capability
@@ -474,6 +475,40 @@ void vp_modern_set_status(struct virtio_pci_modern_device *mdev,
}
EXPORT_SYMBOL_GPL(vp_modern_set_status);

+/*
+ * vp_modern_get_queue_reset - get the queue reset status
+ * @mdev: the modern virtio-pci device
+ * @index: queue index
+ */
+int vp_modern_get_queue_reset(struct virtio_pci_modern_device *mdev, u16 index)
+{
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
+
+ vp_iowrite16(index, &cfg->queue_select);
+ return vp_ioread16(&cfg->queue_reset);
+}
+EXPORT_SYMBOL_GPL(vp_modern_get_queue_reset);
+
+/*
+ * vp_modern_set_queue_reset - reset the queue
+ * @mdev: the modern virtio-pci device
+ * @index: queue index
+ */
+void vp_modern_set_queue_reset(struct virtio_pci_modern_device *mdev, u16 index)
+{
+ struct virtio_pci_common_cfg __iomem *cfg = mdev->common;
+
+ vp_iowrite16(index, &cfg->queue_select);
+ vp_iowrite16(1, &cfg->queue_reset);
+
+ while (vp_ioread16(&cfg->queue_reset))
+ msleep(1);
+
+ while (vp_ioread16(&cfg->queue_enable))
+ msleep(1);
+}
+EXPORT_SYMBOL_GPL(vp_modern_set_queue_reset);
+
/*
* vp_modern_queue_vector - set the MSIX vector for a specific virtqueue
* @mdev: the modern virtio-pci device
diff --git a/include/linux/virtio_pci_modern.h b/include/linux/virtio_pci_modern.h
index beebc7a4a31d..ded01157f864 100644
--- a/include/linux/virtio_pci_modern.h
+++ b/include/linux/virtio_pci_modern.h
@@ -134,4 +134,6 @@ void __iomem * vp_modern_map_vq_notify(struct virtio_pci_modern_device *mdev,
u16 index, resource_size_t *pa);
int vp_modern_probe(struct virtio_pci_modern_device *mdev);
void vp_modern_remove(struct virtio_pci_modern_device *mdev);
+int vp_modern_get_queue_reset(struct virtio_pci_modern_device *mdev, u16 index);
+void vp_modern_set_queue_reset(struct virtio_pci_modern_device *mdev, u16 index);
#endif
--
2.31.0