diff options
Diffstat (limited to 'drivers/xen/grant-dma-ops.c')
-rw-r--r-- | drivers/xen/grant-dma-ops.c | 132 |
1 files changed, 73 insertions, 59 deletions
diff --git a/drivers/xen/grant-dma-ops.c b/drivers/xen/grant-dma-ops.c index 860f37c93af4..9784a77fa3c9 100644 --- a/drivers/xen/grant-dma-ops.c +++ b/drivers/xen/grant-dma-ops.c @@ -10,6 +10,7 @@ #include <linux/module.h> #include <linux/dma-map-ops.h> #include <linux/of.h> +#include <linux/pci.h> #include <linux/pfn.h> #include <linux/xarray.h> #include <linux/virtio_anchor.h> @@ -31,12 +32,12 @@ static DEFINE_XARRAY_FLAGS(xen_grant_dma_devices, XA_FLAGS_LOCK_IRQ); static inline dma_addr_t grant_to_dma(grant_ref_t grant) { - return XEN_GRANT_DMA_ADDR_OFF | ((dma_addr_t)grant << PAGE_SHIFT); + return XEN_GRANT_DMA_ADDR_OFF | ((dma_addr_t)grant << XEN_PAGE_SHIFT); } static inline grant_ref_t dma_to_grant(dma_addr_t dma) { - return (grant_ref_t)((dma & ~XEN_GRANT_DMA_ADDR_OFF) >> PAGE_SHIFT); + return (grant_ref_t)((dma & ~XEN_GRANT_DMA_ADDR_OFF) >> XEN_PAGE_SHIFT); } static struct xen_grant_dma_data *find_xen_grant_dma_data(struct device *dev) @@ -79,7 +80,7 @@ static void *xen_grant_dma_alloc(struct device *dev, size_t size, unsigned long attrs) { struct xen_grant_dma_data *data; - unsigned int i, n_pages = PFN_UP(size); + unsigned int i, n_pages = XEN_PFN_UP(size); unsigned long pfn; grant_ref_t grant; void *ret; @@ -91,14 +92,14 @@ static void *xen_grant_dma_alloc(struct device *dev, size_t size, if (unlikely(data->broken)) return NULL; - ret = alloc_pages_exact(n_pages * PAGE_SIZE, gfp); + ret = alloc_pages_exact(n_pages * XEN_PAGE_SIZE, gfp); if (!ret) return NULL; pfn = virt_to_pfn(ret); if (gnttab_alloc_grant_reference_seq(n_pages, &grant)) { - free_pages_exact(ret, n_pages * PAGE_SIZE); + free_pages_exact(ret, n_pages * XEN_PAGE_SIZE); return NULL; } @@ -116,7 +117,7 @@ static void xen_grant_dma_free(struct device *dev, size_t size, void *vaddr, dma_addr_t dma_handle, unsigned long attrs) { struct xen_grant_dma_data *data; - unsigned int i, n_pages = PFN_UP(size); + unsigned int i, n_pages = XEN_PFN_UP(size); grant_ref_t grant; data = find_xen_grant_dma_data(dev); @@ -138,7 +139,7 @@ static void xen_grant_dma_free(struct device *dev, size_t size, void *vaddr, gnttab_free_grant_reference_seq(grant, n_pages); - free_pages_exact(vaddr, n_pages * PAGE_SIZE); + free_pages_exact(vaddr, n_pages * XEN_PAGE_SIZE); } static struct page *xen_grant_dma_alloc_pages(struct device *dev, size_t size, @@ -168,7 +169,9 @@ static dma_addr_t xen_grant_dma_map_page(struct device *dev, struct page *page, unsigned long attrs) { struct xen_grant_dma_data *data; - unsigned int i, n_pages = PFN_UP(offset + size); + unsigned long dma_offset = xen_offset_in_page(offset), + pfn_offset = XEN_PFN_DOWN(offset); + unsigned int i, n_pages = XEN_PFN_UP(dma_offset + size); grant_ref_t grant; dma_addr_t dma_handle; @@ -187,10 +190,11 @@ static dma_addr_t xen_grant_dma_map_page(struct device *dev, struct page *page, for (i = 0; i < n_pages; i++) { gnttab_grant_foreign_access_ref(grant + i, data->backend_domid, - xen_page_to_gfn(page) + i, dir == DMA_TO_DEVICE); + pfn_to_gfn(page_to_xen_pfn(page) + i + pfn_offset), + dir == DMA_TO_DEVICE); } - dma_handle = grant_to_dma(grant) + offset; + dma_handle = grant_to_dma(grant) + dma_offset; return dma_handle; } @@ -200,8 +204,8 @@ static void xen_grant_dma_unmap_page(struct device *dev, dma_addr_t dma_handle, unsigned long attrs) { struct xen_grant_dma_data *data; - unsigned long offset = dma_handle & (PAGE_SIZE - 1); - unsigned int i, n_pages = PFN_UP(offset + size); + unsigned long dma_offset = xen_offset_in_page(dma_handle); + unsigned int i, n_pages = XEN_PFN_UP(dma_offset + size); grant_ref_t grant; if (WARN_ON(dir == DMA_NONE)) @@ -289,50 +293,48 @@ static const struct dma_map_ops xen_grant_dma_ops = { .dma_supported = xen_grant_dma_supported, }; -static bool xen_is_dt_grant_dma_device(struct device *dev) +static struct device_node *xen_dt_get_node(struct device *dev) { - struct device_node *iommu_np; - bool has_iommu; + if (dev_is_pci(dev)) { + struct pci_dev *pdev = to_pci_dev(dev); + struct pci_bus *bus = pdev->bus; - iommu_np = of_parse_phandle(dev->of_node, "iommus", 0); - has_iommu = iommu_np && - of_device_is_compatible(iommu_np, "xen,grant-dma"); - of_node_put(iommu_np); + /* Walk up to the root bus to look for PCI Host controller */ + while (!pci_is_root_bus(bus)) + bus = bus->parent; - 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) || xen_pv_domain()) - return true; + return of_node_get(bus->bridge->parent->of_node); + } - return xen_is_grant_dma_device(dev->dev.parent); + return of_node_get(dev->of_node); } static int xen_dt_grant_init_backend_domid(struct device *dev, - struct xen_grant_dma_data *data) + struct device_node *np, + domid_t *backend_domid) { - struct of_phandle_args iommu_spec; + struct of_phandle_args iommu_spec = { .args_count = 1 }; - if (of_parse_phandle_with_args(dev->of_node, "iommus", "#iommu-cells", - 0, &iommu_spec)) { - dev_err(dev, "Cannot parse iommus property\n"); - return -ESRCH; + if (dev_is_pci(dev)) { + struct pci_dev *pdev = to_pci_dev(dev); + u32 rid = PCI_DEVID(pdev->bus->number, pdev->devfn); + + if (of_map_id(np, rid, "iommu-map", "iommu-map-mask", &iommu_spec.np, + iommu_spec.args)) { + dev_dbg(dev, "Cannot translate ID\n"); + return -ESRCH; + } + } else { + if (of_parse_phandle_with_args(np, "iommus", "#iommu-cells", + 0, &iommu_spec)) { + dev_dbg(dev, "Cannot parse iommus property\n"); + 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"); + dev_dbg(dev, "Incompatible IOMMU node\n"); of_node_put(iommu_spec.np); return -ESRCH; } @@ -343,12 +345,31 @@ static int xen_dt_grant_init_backend_domid(struct device *dev, * The endpoint ID here means the ID of the domain where the * corresponding backend is running */ - data->backend_domid = iommu_spec.args[0]; + *backend_domid = iommu_spec.args[0]; return 0; } -void xen_grant_setup_dma_ops(struct device *dev) +static int xen_grant_init_backend_domid(struct device *dev, + domid_t *backend_domid) +{ + struct device_node *np; + int ret = -ENODEV; + + np = xen_dt_get_node(dev); + if (np) { + ret = xen_dt_grant_init_backend_domid(dev, np, backend_domid); + of_node_put(np); + } else if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT) || xen_pv_domain()) { + dev_info(dev, "Using dom0 as backend\n"); + *backend_domid = 0; + ret = 0; + } + + return ret; +} + +static void xen_grant_setup_dma_ops(struct device *dev, domid_t backend_domid) { struct xen_grant_dma_data *data; @@ -362,16 +383,7 @@ void xen_grant_setup_dma_ops(struct device *dev) if (!data) goto err; - if (dev->of_node) { - if (xen_dt_grant_init_backend_domid(dev, data)) - goto err; - } else if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT)) { - dev_info(dev, "Using dom0 as backend\n"); - data->backend_domid = 0; - } else { - /* XXX ACPI device unsupported for now */ - goto err; - } + data->backend_domid = backend_domid; if (store_xen_grant_dma_data(dev, data)) { dev_err(dev, "Cannot store Xen grant DMA data\n"); @@ -389,12 +401,14 @@ err: bool xen_virtio_restricted_mem_acc(struct virtio_device *dev) { - bool ret = xen_virtio_mem_acc(dev); + domid_t backend_domid; - if (ret) - xen_grant_setup_dma_ops(dev->dev.parent); + if (!xen_grant_init_backend_domid(dev->dev.parent, &backend_domid)) { + xen_grant_setup_dma_ops(dev->dev.parent, backend_domid); + return true; + } - return ret; + return false; } MODULE_DESCRIPTION("Xen grant DMA-mapping layer"); |