drm/mm: fix dump table BUG

In

commit 9e8944ab564f2e3dde90a518cd32048c58918608
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Thu Nov 15 11:32:17 2012 +0000

    drm: Introduce an iterator over holes in the drm_mm range manager

helpers and iterators for hole handling have been introduced with some
debug BUG_ONs sprinkled over. Unfortunately this broke the mm dumper
which unconditionally tried to compute the size of the very first
hole.

While at it unify the code a bit with the hole dumping in the loop.

v2: Extract a hole dump helper.

Reported-by: Christopher Harvey <charvey@matrox.com>
Cc: Christopher Harvey <charvey@matrox.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: stable@vger.kernel.org
Acked-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c
index db1e2d6f90d7221d713c04b70560d85a08ad6732..07cf99cc886283aedf9feee690d71ee6fbe2fb77 100644 (file)
--- a/drivers/gpu/drm/drm_mm.c
+++ b/drivers/gpu/drm/drm_mm.c
@@ -755,33 +755,35 @@ void drm_mm_debug_table(struct drm_mm *mm, const char *prefix)
 EXPORT_SYMBOL(drm_mm_debug_table);
 
 #if defined(CONFIG_DEBUG_FS)
-int drm_mm_dump_table(struct seq_file *m, struct drm_mm *mm)
+static unsigned long drm_mm_dump_hole(struct seq_file *m, struct drm_mm_node *entry)
 {
-       struct drm_mm_node *entry;
-       unsigned long total_used = 0, total_free = 0, total = 0;
        unsigned long hole_start, hole_end, hole_size;
 
-       hole_start = drm_mm_hole_node_start(&mm->head_node);
-       hole_end = drm_mm_hole_node_end(&mm->head_node);
-       hole_size = hole_end - hole_start;
-       if (hole_size)
+       if (entry->hole_follows) {
+               hole_start = drm_mm_hole_node_start(entry);
+               hole_end = drm_mm_hole_node_end(entry);
+               hole_size = hole_end - hole_start;
                seq_printf(m, "0x%08lx-0x%08lx: 0x%08lx: free\n",
                                hole_start, hole_end, hole_size);
-       total_free += hole_size;
+               return hole_size;
+       }
+
+       return 0;
+}
+
+int drm_mm_dump_table(struct seq_file *m, struct drm_mm *mm)
+{
+       struct drm_mm_node *entry;
+       unsigned long total_used = 0, total_free = 0, total = 0;
+
+       total_free += drm_mm_dump_hole(m, &mm->head_node);
 
        drm_mm_for_each_node(entry, mm) {
                seq_printf(m, "0x%08lx-0x%08lx: 0x%08lx: used\n",
                                entry->start, entry->start + entry->size,
                                entry->size);
                total_used += entry->size;
-               if (entry->hole_follows) {
-                       hole_start = drm_mm_hole_node_start(entry);
-                       hole_end = drm_mm_hole_node_end(entry);
-                       hole_size = hole_end - hole_start;
-                       seq_printf(m, "0x%08lx-0x%08lx: 0x%08lx: free\n",
-                                       hole_start, hole_end, hole_size);
-                       total_free += hole_size;
-               }
+               total_free += drm_mm_dump_hole(m, entry);
        }
        total = total_free + total_used;