From c9133112f347907774055bbf73179a7ff8504689 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Mon, 29 Aug 2022 13:26:07 +0200 Subject: xen/virtio: restructure xen grant dma setup In order to prepare supporting other means than device tree for setting up virtio devices under Xen, restructure the functions xen_is_grant_dma_device() and xen_grant_setup_dma_ops() a little bit. Signed-off-by: Juergen Gross Reviewed-by: Oleksandr Tyshchenko Tested-by: Oleksandr Tyshchenko # Arm64 only Acked-by: Stefano Stabellini Signed-off-by: Juergen Gross --- drivers/xen/grant-dma-ops.c | 68 ++++++++++++++++++++++++++++----------------- 1 file changed, 43 insertions(+), 25 deletions(-) (limited to 'drivers/xen') diff --git a/drivers/xen/grant-dma-ops.c b/drivers/xen/grant-dma-ops.c index c66f56d24013..7133272918f0 100644 --- a/drivers/xen/grant-dma-ops.c +++ b/drivers/xen/grant-dma-ops.c @@ -289,22 +289,28 @@ static const struct dma_map_ops xen_grant_dma_ops = { .dma_supported = xen_grant_dma_supported, }; -bool xen_is_grant_dma_device(struct device *dev) +static bool xen_is_dt_grant_dma_device(struct device *dev) { struct device_node *iommu_np; bool has_iommu; - /* XXX Handle only DT devices for now */ - if (!dev->of_node) - return false; - iommu_np = of_parse_phandle(dev->of_node, "iommus", 0); - has_iommu = iommu_np && of_device_is_compatible(iommu_np, "xen,grant-dma"); + has_iommu = iommu_np && + of_device_is_compatible(iommu_np, "xen,grant-dma"); of_node_put(iommu_np); return has_iommu; } +bool xen_is_grant_dma_device(struct device *dev) +{ + /* XXX Handle only DT devices for now */ + if (dev->of_node) + return xen_is_dt_grant_dma_device(dev); + + return false; +} + bool xen_virtio_mem_acc(struct virtio_device *dev) { if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT)) @@ -313,45 +319,56 @@ bool xen_virtio_mem_acc(struct virtio_device *dev) return xen_is_grant_dma_device(dev->dev.parent); } -void xen_grant_setup_dma_ops(struct device *dev) +static int xen_dt_grant_init_backend_domid(struct device *dev, + struct xen_grant_dma_data *data) { - struct xen_grant_dma_data *data; struct of_phandle_args iommu_spec; - data = find_xen_grant_dma_data(dev); - if (data) { - dev_err(dev, "Xen grant DMA data is already created\n"); - return; - } - - /* XXX ACPI device unsupported for now */ - if (!dev->of_node) - goto err; - if (of_parse_phandle_with_args(dev->of_node, "iommus", "#iommu-cells", 0, &iommu_spec)) { dev_err(dev, "Cannot parse iommus property\n"); - goto err; + return -ESRCH; } if (!of_device_is_compatible(iommu_spec.np, "xen,grant-dma") || iommu_spec.args_count != 1) { dev_err(dev, "Incompatible IOMMU node\n"); of_node_put(iommu_spec.np); - goto err; + return -ESRCH; } of_node_put(iommu_spec.np); + /* + * The endpoint ID here means the ID of the domain where the + * corresponding backend is running + */ + data->backend_domid = iommu_spec.args[0]; + + return 0; +} + +void xen_grant_setup_dma_ops(struct device *dev) +{ + struct xen_grant_dma_data *data; + + data = find_xen_grant_dma_data(dev); + if (data) { + dev_err(dev, "Xen grant DMA data is already created\n"); + return; + } + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); if (!data) goto err; - /* - * The endpoint ID here means the ID of the domain where the corresponding - * backend is running - */ - data->backend_domid = iommu_spec.args[0]; + if (dev->of_node) { + if (xen_dt_grant_init_backend_domid(dev, data)) + goto err; + } else { + /* XXX ACPI device unsupported for now */ + goto err; + } if (store_xen_grant_dma_data(dev, data)) { dev_err(dev, "Cannot store Xen grant DMA data\n"); @@ -363,6 +380,7 @@ void xen_grant_setup_dma_ops(struct device *dev) return; err: + devm_kfree(dev, data); dev_err(dev, "Cannot set up Xen grant DMA ops, retain platform DMA ops\n"); } -- cgit v1.2.3