[PATCH 07/12] libxl: Allow stubdomain to control interupts of PCI device

[Marek Marczykowski-Górecki <marmarek@xxxxxxxxxxxxxxxxxxxxxx>]

Especially allow it to control MSI/MSI-X enabling bits. This part only
writes a flag to a sysfs, the actual implementation is on the kernel
side.

This requires Linux >= 5.10 in dom0 (or relevant patch backported).

Signed-off-by: Marek Marczykowski-Górecki <marmarek@xxxxxxxxxxxxxxxxxxxxxx>
---
 tools/libs/light/libxl_pci.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/tools/libs/light/libxl_pci.c b/tools/libs/light/libxl_pci.c
index 96cb4da0794e..6f357b70b815 100644
--- a/tools/libs/light/libxl_pci.c
+++ b/tools/libs/light/libxl_pci.c
@@ -1513,6 +1513,14 @@ static void pci_add_dm_done(libxl__egc *egc,
             rc = ERROR_FAIL;
             goto out;
         }
+    } else if (libxl_is_stubdom(ctx, domid, NULL)) {
+        /* Allow acces to MSI enable flag in PCI config space for the stubdom 
*/
+        if ( sysfs_write_bdf(gc, 
SYSFS_PCIBACK_DRIVER"/allow_interrupt_control",
+                             pci) < 0 ) {
+            LOGD(ERROR, domainid, "Setting allow_interrupt_control for 
device");
+            rc = ERROR_FAIL;
+            goto out;
+        }
     }
 
 out_no_irq:
-- 
git-series 0.9.1