xfree86: Add ModulePath support for OutputClass config Sections

Allow OutputClass config snippets to modify the module-path.

Note that any specified ModulePaths will be pre-pended to the normal
ModulePath. The idea behind this is that any output hardware specific
modules should have preference over the normal modules.

One use-case for this is the nvidia binary driver, this allows a
config snippet like this:

Section "OutputClass"
    MatchDriver "nvidia"
    Modulepath "/usr/lib64/nvidia/modules"
EndSection

To get the nvidia glx specific glx module loaded, but only when the
nvidia kernel driver is loaded.

Together with the glvnd work done recently, this allows the nouveau
+ mesa and nvidia-binary userspace stacks to co-exist on the same
system without any ldconfig / xorg.conf tweaking and the xserver will
automatically do the right thing depending on which kernel driver
(nouveau or nvidia) is loaded.

Reviewed-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
(cherry picked from commit b5dffbbac193aa640ffcfa0a431c21b862854e53)

1 files changed, 23 insertions, 0 deletions

diff --git a/hw/xfree86/common/xf86platformBus.c b/hw/xfree86/common/xf86platformBus.c
index fc17d1504..0b5795fe7 100644
--- a/hw/xfree86/common/xf86platformBus.c
+++ b/hw/xfree86/common/xf86platformBus.c
@@ -40,6 +40,7 @@
 #include "hotplug.h"
 #include "systemd-logind.h"
 
+#include "loaderProcs.h"
 #include "xf86.h"
 #include "xf86_OSproc.h"
 #include "xf86Priv.h"
@@ -287,6 +288,7 @@ xf86platformProbe(void)
     int i;
     Bool pci = TRUE;
     XF86ConfOutputClassPtr cl;
+    char *old_path, *path = NULL;
 
     config_odev_probe(xf86PlatformDeviceProbe);
 
@@ -300,8 +302,29 @@ xf86platformProbe(void)
         if (pci && (strncmp(busid, "pci:", 4) == 0)) {
             platform_find_pci_info(&xf86_platform_devices[i], busid);
         }
+
+        /*
+         * Deal with OutputClass ModulePath directives, these must be
+         * processed before we do any module loading.
+         */
+        for (cl = xf86configptr->conf_outputclass_lst; cl; cl = cl->list.next) {
+            if (!OutputClassMatches(cl, &xf86_platform_devices[i]))
+                continue;
+
+            if (cl->modulepath && xf86ModPathFrom != X_CMDLINE) {
+                old_path = path;
+                XNFasprintf(&path, "%s,%s", cl->modulepath,
+                            path ? path : xf86ModulePath);
+                free(old_path);
+                xf86Msg(X_CONFIG, "OutputClass \"%s\" ModulePath extended to \"%s\"\n",
+                        cl->identifier, path);
+                LoaderSetPath(path);
+            }
+        }
     }
 
+    free(path);
+
     /* First see if there is an OutputClass match marking a device as primary */
     for (i = 0; i < xf86_num_platform_devices; i++) {
         struct xf86_platform_device *dev = &xf86_platform_devices[i];