0620-libxl-Allow-stubdomain-to-control-interupts-of-PCI-d.patch

From b264671e40262b0e81cf7b1badef2a4da3837946 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marek=20Marczykowski-G=C3=B3recki?=
 <marmarek@invisiblethingslab.com>
Date: Wed, 16 Nov 2022 01:31:42 +0100
Subject: [PATCH] libxl: Allow stubdomain to control interupts of PCI device
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

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.

Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
---
 tools/libs/light/libxl_pci.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/tools/libs/light/libxl_pci.c b/tools/libs/light/libxl_pci.c
index bf4acb46d6e8..e87c58100127 100644
--- a/tools/libs/light/libxl_pci.c
+++ b/tools/libs/light/libxl_pci.c
@@ -1512,6 +1512,17 @@ 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 ) {
+            if ( sysfs_write_bdf(gc, SYSFS_PCIBACK_DRIVER"/allow_msi_enable",
+                                 pci) < 0 ) {
+                LOGD(ERROR, domainid, "Setting allow_msi_enable for device");
+                rc = ERROR_FAIL;
+                goto out;
+            }
+        }
     }
 
 out_no_irq:
-- 
2.44.0