hw/xen: Add "mode" parameter to xen-block devices

dwmw2 · tperard · commit 4173b3d83752 · 2025-03-10T13:27:30.000+01:00
Block devices don't work in PV Grub (0.9x) if there is no mode specified. It
complains: "Error ENOENT when reading the mode"

Signed-off-by: David Woodhouse &lt;dwmw@amazon.co.uk&gt;
Message-Id: &lt;20250207143724.30792-2-dwmw2@infradead.org&gt;
Signed-off-by: Anthony PERARD &lt;anthony.perard@vates.tech&gt;
diff --git a/hw/block/xen-block.c b/hw/block/xen-block.c
@@ -408,6 +408,8 @@ static void xen_block_realize(XenDevice *xendev, Error **errp)
     }
 
     xen_device_backend_printf(xendev, "info", "%u", blockdev->info);
+    xen_device_backend_printf(xendev, "mode",
+                              (blockdev->info & VDISK_READONLY) ? "r" : "w");
 
     xen_device_frontend_printf(xendev, "virtual-device", "%lu",
                                vdev->number);

Original file line number	Diff line number	Diff line change
`@@ -408,6 +408,8 @@ static void xen_block_realize(XenDevice xendev, Error *errp)`
`408`	`408`	`}`
`409`	`409`
`410`	`410`	`xen_device_backend_printf(xendev, "info", "%u", blockdev->info);`
	`411`	`+ xen_device_backend_printf(xendev, "mode",`
	`412`	`+ (blockdev->info & VDISK_READONLY) ? "r" : "w");`
`411`	`413`
`412`	`414`	`xen_device_frontend_printf(xendev, "virtual-device", "%lu",`
`413`	`415`	`vdev->number);`