xf86drm: adjust device node path for minor base
When constructing a path to a device node the minor number retrieved
from fstat needs to have the offset of the node type subtracted from it.
Control and render node types have the same major as the primary node
but each has their own block of minor types at fixed offsets.
v2: remove min < base test as requested by Emil
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Jonathan Gray <jsg@jsg.id.au>
diff --git a/xf86drm.c b/xf86drm.c
index b5eeeb0..f6850aa 100644
--- a/xf86drm.c
+++ b/xf86drm.c
@@ -2838,7 +2838,7 @@
char buf[PATH_MAX + 1];
const char *dev_name;
unsigned int maj, min;
- int n;
+ int n, base;
if (fstat(fd, &sbuf))
return NULL;
@@ -2863,7 +2863,11 @@
return NULL;
};
- n = snprintf(buf, sizeof(buf), dev_name, DRM_DIR_NAME, min);
+ base = drmGetMinorBase(type);
+ if (base < 0)
+ return NULL;
+
+ n = snprintf(buf, sizeof(buf), dev_name, DRM_DIR_NAME, min - base);
if (n == -1 || n >= sizeof(buf))
return NULL;
@@ -3262,7 +3266,7 @@
char node[PATH_MAX + 1];
const char *dev_name;
int node_type, subsystem_type;
- int maj, min, n, ret;
+ int maj, min, n, ret, base;
if (fd == -1 || device == NULL)
return -EINVAL;
@@ -3294,7 +3298,11 @@
return -EINVAL;
};
- n = snprintf(node, PATH_MAX, dev_name, DRM_DIR_NAME, min);
+ base = drmGetMinorBase(node_type);
+ if (base < 0)
+ return -EINVAL;
+
+ n = snprintf(node, PATH_MAX, dev_name, DRM_DIR_NAME, min - base);
if (n == -1 || n >= PATH_MAX)
return -errno;
if (stat(node, &sbuf))