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authorOleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>2021-10-28 17:36:20 +0300
committerBoris Ostrovsky <boris.ostrovsky@oracle.com>2021-11-02 08:03:43 -0500
commita67efff28832a597f46a0097916833937aa3983e (patch)
treea7f1565499eaad3156048e22c630da69d49ed4dc /drivers/xen/xen-pciback/pciback.h
parente453f872b72fb93e54ab0f3a07eeeacc2215fd15 (diff)
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xen-pciback: allow compiling on other archs than x86
Xen-pciback driver was designed to be built for x86 only. But it can also be used by other architectures, e.g. Arm. Currently PCI backend implements multiple functionalities at a time, such as: 1. It is used as a database for assignable PCI devices, e.g. xl pci-assignable-{add|remove|list} manipulates that list. So, whenever the toolstack needs to know which PCI devices can be passed through it reads that from the relevant sysfs entries of the pciback. 2. It is used to hold the unbound PCI devices list, e.g. when passing through a PCI device it needs to be unbound from the relevant device driver and bound to pciback (strictly speaking it is not required that the device is bound to pciback, but pciback is again used as a database of the passed through PCI devices, so we can re-bind the devices back to their original drivers when guest domain shuts down) 3. Device reset for the devices being passed through 4. Para-virtualised use-cases support The para-virtualised part of the driver is not always needed as some architectures, e.g. Arm or x86 PVH Dom0, are not using backend-frontend model for PCI device passthrough. For such use-cases make the very first step in splitting the xen-pciback driver into two parts: Xen PCI stub and PCI PV backend drivers. For that add new configuration options CONFIG_XEN_PCI_STUB and CONFIG_XEN_PCIDEV_STUB, so the driver can be limited in its functionality, e.g. no support for para-virtualised scenario. x86 platform will continue using CONFIG_XEN_PCIDEV_BACKEND for the fully featured backend driver. Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> Signed-off-by: Anastasiia Lukianenko <anastasiia_lukianenko@epam.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Reviewed-by: Juergen Gross <jgross@suse.com> Link: https://lore.kernel.org/r/20211028143620.144936-1-andr2000@gmail.com Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Diffstat (limited to 'drivers/xen/xen-pciback/pciback.h')
-rw-r--r--drivers/xen/xen-pciback/pciback.h5
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/xen/xen-pciback/pciback.h b/drivers/xen/xen-pciback/pciback.h
index 95e28ee48d52..9a64196e831d 100644
--- a/drivers/xen/xen-pciback/pciback.h
+++ b/drivers/xen/xen-pciback/pciback.h
@@ -71,6 +71,11 @@ struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev,
struct pci_dev *dev);
void pcistub_put_pci_dev(struct pci_dev *dev);
+static inline bool xen_pcibk_pv_support(void)
+{
+ return IS_ENABLED(CONFIG_XEN_PCIDEV_BACKEND);
+}
+
/* Ensure a device is turned off or reset */
void xen_pcibk_reset_device(struct pci_dev *pdev);