From: Maxime Coquelin <maxime.coquelin@redhat.com>
Date: Tue, 26 Jan 2021 10:15:57 +0000 (+0100)
Subject: bus/vdev: add driver IOVA VA mode requirement
X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=8d935fff55469367f459e71a480ec0fbf7e85daa;p=dpdk.git

bus/vdev: add driver IOVA VA mode requirement

This patch adds driver flag in vdev bus driver so that
vdev drivers can require VA IOVA mode to be used, which
for example the case of Virtio-user PMD.

The patch implements the .get_iommu_class() callback, that
is called before devices probing to determine the IOVA mode
to be used, and adds a check right before the device is
probed to ensure compatible IOVA mode has been selected.

It also adds a ABI exception rule to accommodate with an
update on the driver registration API

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Acked-by: David Marchand <david.marchand@redhat.com>
Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>
---

diff --git a/devtools/libabigail.abignore b/devtools/libabigail.abignore
index 9e06bbed92..ab5db240e7 100644
--- a/devtools/libabigail.abignore
+++ b/devtools/libabigail.abignore
@@ -15,6 +15,8 @@
 ; Explicit ignore for driver-only ABI
 [suppress_type]
         name = eth_dev_ops
+[suppress_function]
+        name_regexp = rte_vdev_(|un)register
 
 ; Ignore fields inserted in cacheline boundary of rte_cryptodev
 [suppress_type]
diff --git a/drivers/bus/vdev/rte_bus_vdev.h b/drivers/bus/vdev/rte_bus_vdev.h
index f99a41f825..fc315d10fa 100644
--- a/drivers/bus/vdev/rte_bus_vdev.h
+++ b/drivers/bus/vdev/rte_bus_vdev.h
@@ -113,8 +113,12 @@ struct rte_vdev_driver {
 	rte_vdev_remove_t *remove;       /**< Virtual device remove function. */
 	rte_vdev_dma_map_t *dma_map;     /**< Virtual device DMA map function. */
 	rte_vdev_dma_unmap_t *dma_unmap; /**< Virtual device DMA unmap function. */
+	uint32_t drv_flags;              /**< Flags RTE_VDEV_DRV_*. */
 };
 
+/** Device driver needs IOVA as VA and cannot work with IOVA as PA */
+#define RTE_VDEV_DRV_NEED_IOVA_AS_VA 0x0001
+
 /**
  * Register a virtual device driver.
  *
diff --git a/drivers/bus/vdev/vdev.c b/drivers/bus/vdev/vdev.c
index acfd78828f..9a673347ae 100644
--- a/drivers/bus/vdev/vdev.c
+++ b/drivers/bus/vdev/vdev.c
@@ -189,6 +189,7 @@ vdev_probe_all_drivers(struct rte_vdev_device *dev)
 {
 	const char *name;
 	struct rte_vdev_driver *driver;
+	enum rte_iova_mode iova_mode;
 	int ret;
 
 	if (rte_dev_is_probed(&dev->device))
@@ -199,6 +200,14 @@ vdev_probe_all_drivers(struct rte_vdev_device *dev)
 
 	if (vdev_parse(name, &driver))
 		return -1;
+
+	iova_mode = rte_eal_iova_mode();
+	if ((driver->drv_flags & RTE_VDEV_DRV_NEED_IOVA_AS_VA) && (iova_mode == RTE_IOVA_PA)) {
+		VDEV_LOG(ERR, "%s requires VA IOVA mode but current mode is PA, not initializing",
+				name);
+		return -1;
+	}
+
 	ret = driver->probe(dev);
 	if (ret == 0)
 		dev->device.driver = &driver->driver;
@@ -594,6 +603,25 @@ vdev_unplug(struct rte_device *dev)
 	return rte_vdev_uninit(dev->name);
 }
 
+static enum rte_iova_mode
+vdev_get_iommu_class(void)
+{
+	const char *name;
+	struct rte_vdev_device *dev;
+	struct rte_vdev_driver *driver;
+
+	TAILQ_FOREACH(dev, &vdev_device_list, next) {
+		name = rte_vdev_device_name(dev);
+		if (vdev_parse(name, &driver))
+			continue;
+
+		if (driver->drv_flags & RTE_VDEV_DRV_NEED_IOVA_AS_VA)
+			return RTE_IOVA_VA;
+	}
+
+	return RTE_IOVA_DC;
+}
+
 static struct rte_bus rte_vdev_bus = {
 	.scan = vdev_scan,
 	.probe = vdev_probe,
@@ -603,6 +631,7 @@ static struct rte_bus rte_vdev_bus = {
 	.parse = vdev_parse,
 	.dma_map = vdev_dma_map,
 	.dma_unmap = vdev_dma_unmap,
+	.get_iommu_class = vdev_get_iommu_class,
 	.dev_iterate = rte_vdev_dev_iterate,
 };