gpu: nvgpu: free global ctx bufs only if allocated

Try to free only allocated buffers in
gr_gk20a_free_global_ctx_buffers(), otherwise the destroy function
pointer would be NULL and crash for nonallocated buffers. This can
happen when init fails for some of the buffers. Additionally, make the
pointer NULL when a buffer is destroyed, to signify this state.

Also refactor the function upwards and call it from
gr_gk20a_alloc_global_ctx_buffers() to reduce code duplication.

Change-Id: I6e74795014f5e315b5f8342f544ddfccc0d02b71
Signed-off-by: Konsta Holtta <kholtta@nvidia.com>
Reviewed-on: http://git-master/r/1126026
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Tested-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 19 insertions, 23 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/gr_gk20a.c b/drivers/gpu/nvgpu/gk20a/gr_gk20a.c
index d085e96f..5317bd87 100644
--- a/drivers/gpu/nvgpu/gk20a/gr_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/gr_gk20a.c
@@ -2419,6 +2419,7 @@ static void gk20a_gr_destroy_ctx_buffer(struct gk20a *g,
         if (!desc)
                 return;
         gk20a_gmmu_free_attr(g, DMA_ATTR_NO_KERNEL_MAPPING, &desc->mem);
+        desc->destroy = NULL;
 }
 
 static int gk20a_gr_alloc_ctx_buffer(struct gk20a *g,
@@ -2437,11 +2438,27 @@ static int gk20a_gr_alloc_ctx_buffer(struct gk20a *g,
         return err;
 }
 
+static void gr_gk20a_free_global_ctx_buffers(struct gk20a *g)
+{
+        struct gr_gk20a *gr = &g->gr;
+        u32 i;
+
+        for (i = 0; i < NR_GLOBAL_CTX_BUF; i++) {
+                /* destroy exists iff buffer is allocated */
+                if (gr->global_ctx_buffer[i].destroy) {
+                        gr->global_ctx_buffer[i].destroy(g,
+                                        &gr->global_ctx_buffer[i]);
+                }
+        }
+
+        gk20a_dbg_fn("done");
+}
+
 static int gr_gk20a_alloc_global_ctx_buffers(struct gk20a *g)
 {
         struct gk20a_platform *platform = dev_get_drvdata(g->dev);
         struct gr_gk20a *gr = &g->gr;
-        int i, attr_buffer_size, err;
+        int attr_buffer_size, err;
         struct device *dev = g->dev;
 
         u32 cb_buffer_size = gr->bundle_cb_default_size *
@@ -2517,31 +2534,10 @@ static int gr_gk20a_alloc_global_ctx_buffers(struct gk20a *g)
 
  clean_up:
         gk20a_err(dev_from_gk20a(g), "fail");
-        for (i = 0; i < NR_GLOBAL_CTX_BUF; i++) {
-                if (gr->global_ctx_buffer[i].destroy) {
-                        gr->global_ctx_buffer[i].destroy(g,
-                                        &gr->global_ctx_buffer[i]);
-                }
-        }
+        gr_gk20a_free_global_ctx_buffers(g);
         return -ENOMEM;
 }
 
-static void gr_gk20a_free_global_ctx_buffers(struct gk20a *g)
-{
-        struct gr_gk20a *gr = &g->gr;
-        DEFINE_DMA_ATTRS(attrs);
-        u32 i;
-
-        dma_set_attr(DMA_ATTR_NO_KERNEL_MAPPING, &attrs);
-
-        for (i = 0; i < NR_GLOBAL_CTX_BUF; i++) {
-                gr->global_ctx_buffer[i].destroy(g,
-                                &gr->global_ctx_buffer[i]);
-        }
-
-        gk20a_dbg_fn("done");
-}
-
 static int gr_gk20a_map_global_ctx_buffers(struct gk20a *g,
                                         struct channel_gk20a *c)
 {