diff options
Diffstat (limited to 'drivers/pci/ats.c')
| -rw-r--r-- | drivers/pci/ats.c | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c index 390e92f2d8d1..b761c1f72f67 100644 --- a/drivers/pci/ats.c +++ b/drivers/pci/ats.c @@ -31,6 +31,22 @@ void pci_ats_init(struct pci_dev *dev) } /** + * pci_ats_supported - check if the device can use ATS + * @dev: the PCI device + * + * Returns true if the device supports ATS and is allowed to use it, false + * otherwise. + */ +bool pci_ats_supported(struct pci_dev *dev) +{ + if (!dev->ats_cap) + return false; + + return (dev->untrusted == 0); +} +EXPORT_SYMBOL_GPL(pci_ats_supported); + +/** * pci_enable_ats - enable the ATS capability * @dev: the PCI device * @ps: the IOMMU page shift @@ -42,7 +58,7 @@ int pci_enable_ats(struct pci_dev *dev, int ps) u16 ctrl; struct pci_dev *pdev; - if (!dev->ats_cap) + if (!pci_ats_supported(dev)) return -EINVAL; if (WARN_ON(dev->ats_enabled)) |