diff options
Diffstat (limited to 'drivers/xen/grant-dma-ops.c')
-rw-r--r-- | drivers/xen/grant-dma-ops.c | 133 |
1 files changed, 91 insertions, 42 deletions
diff --git a/drivers/xen/grant-dma-ops.c b/drivers/xen/grant-dma-ops.c index 8973fc1e9ccc..daa525df7bdc 100644 --- a/drivers/xen/grant-dma-ops.c +++ b/drivers/xen/grant-dma-ops.c @@ -25,31 +25,46 @@ struct xen_grant_dma_data { bool broken; }; -static DEFINE_XARRAY(xen_grant_dma_devices); +static DEFINE_XARRAY_FLAGS(xen_grant_dma_devices, XA_FLAGS_LOCK_IRQ); #define XEN_GRANT_DMA_ADDR_OFF (1ULL << 63) 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) { struct xen_grant_dma_data *data; + unsigned long flags; - xa_lock(&xen_grant_dma_devices); + xa_lock_irqsave(&xen_grant_dma_devices, flags); data = xa_load(&xen_grant_dma_devices, (unsigned long)dev); - xa_unlock(&xen_grant_dma_devices); + xa_unlock_irqrestore(&xen_grant_dma_devices, flags); return data; } +static int store_xen_grant_dma_data(struct device *dev, + struct xen_grant_dma_data *data) +{ + unsigned long flags; + int ret; + + xa_lock_irqsave(&xen_grant_dma_devices, flags); + ret = xa_err(__xa_store(&xen_grant_dma_devices, (unsigned long)dev, data, + GFP_ATOMIC)); + xa_unlock_irqrestore(&xen_grant_dma_devices, flags); + + return ret; +} + /* * DMA ops for Xen frontends (e.g. virtio). * @@ -64,7 +79,7 @@ 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; @@ -76,14 +91,14 @@ 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; } @@ -101,7 +116,7 @@ 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); @@ -123,7 +138,7 @@ 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, @@ -153,7 +168,9 @@ 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(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; @@ -172,10 +189,11 @@ 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; } @@ -185,7 +203,8 @@ 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 int i, n_pages = PFN_UP(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)) @@ -273,72 +292,91 @@ 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)) + if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT) || xen_pv_domain()) return true; 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 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; + } - if (xa_err(xa_store(&xen_grant_dma_devices, (unsigned long)dev, data, - GFP_KERNEL))) { + if (store_xen_grant_dma_data(dev, data)) { dev_err(dev, "Cannot store Xen grant DMA data\n"); goto err; } @@ -348,9 +386,20 @@ 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"); } +bool xen_virtio_restricted_mem_acc(struct virtio_device *dev) +{ + bool ret = xen_virtio_mem_acc(dev); + + if (ret) + xen_grant_setup_dma_ops(dev->dev.parent); + + return ret; +} + MODULE_DESCRIPTION("Xen grant DMA-mapping layer"); MODULE_AUTHOR("Juergen Gross <jgross@suse.com>"); MODULE_LICENSE("GPL"); |