3 files changed, 9 insertions, 3 deletions

diff --git a/drivers/gpu/nvgpu/common/linux/ioctl_as.c b/drivers/gpu/nvgpu/common/linux/ioctl_as.c
index f23dc53c..848fee04 100644
--- a/drivers/gpu/nvgpu/common/linux/ioctl_as.c
+++ b/drivers/gpu/nvgpu/common/linux/ioctl_as.c
@@ -112,7 +112,6 @@ static int gk20a_as_ioctl_map_buffer_batch(
         struct gk20a_as_share *as_share,
         struct nvgpu_as_map_buffer_batch_args *args)
 {
-        struct gk20a *g = as_share->vm->mm->g;
         u32 i;
         int err = 0;
 
@@ -127,8 +126,8 @@ static int gk20a_as_ioctl_map_buffer_batch(
 
         gk20a_dbg_fn("");
 
-        if (args->num_unmaps > g->gpu_characteristics.map_buffer_batch_limit ||
-            args->num_maps > g->gpu_characteristics.map_buffer_batch_limit)
+        if (args->num_unmaps > NVGPU_IOCTL_AS_MAP_BUFFER_BATCH_LIMIT ||
+            args->num_maps > NVGPU_IOCTL_AS_MAP_BUFFER_BATCH_LIMIT)
                 return -EINVAL;
 
         nvgpu_vm_mapping_batch_start(&batch);
diff --git a/drivers/gpu/nvgpu/common/linux/ioctl_as.h b/drivers/gpu/nvgpu/common/linux/ioctl_as.h
index ae6690a1..b3de3782 100644
--- a/drivers/gpu/nvgpu/common/linux/ioctl_as.h
+++ b/drivers/gpu/nvgpu/common/linux/ioctl_as.h
@@ -18,6 +18,10 @@
 struct inode;
 struct file;
 
+/* MAP_BUFFER_BATCH_LIMIT: the upper limit for num_unmaps and
+ * num_maps */
+#define NVGPU_IOCTL_AS_MAP_BUFFER_BATCH_LIMIT   256
+
 /* struct file_operations driver interface */
 int gk20a_as_dev_open(struct inode *inode, struct file *filp);
 int gk20a_as_dev_release(struct inode *inode, struct file *filp);
diff --git a/drivers/gpu/nvgpu/common/linux/ioctl_ctrl.c b/drivers/gpu/nvgpu/common/linux/ioctl_ctrl.c
index 3c6b1b26..b77855f4 100644
--- a/drivers/gpu/nvgpu/common/linux/ioctl_ctrl.c
+++ b/drivers/gpu/nvgpu/common/linux/ioctl_ctrl.c
@@ -34,6 +34,7 @@
 
 #include "ioctl_ctrl.h"
 #include "ioctl_dbg.h"
+#include "ioctl_as.h"
 #ifdef CONFIG_TEGRA_19x_GPU
 #include "common/linux/ioctl_ctrl_t19x.h"
 #endif
@@ -209,6 +210,8 @@ gk20a_ctrl_ioctl_gpu_characteristics(
         pgpu->impl = g->params.gpu_impl;
         pgpu->rev = g->params.gpu_rev;
         pgpu->reg_ops_limit = NVGPU_IOCTL_DBG_REG_OPS_LIMIT;
+        pgpu->map_buffer_batch_limit = nvgpu_is_enabled(g, NVGPU_SUPPORT_MAP_BUFFER_BATCH) ?
+                NVGPU_IOCTL_AS_MAP_BUFFER_BATCH_LIMIT : 0;
         pgpu->twod_class = g->ops.get_litter_value(g, GPU_LIT_TWOD_CLASS);
         pgpu->threed_class = g->ops.get_litter_value(g, GPU_LIT_THREED_CLASS);
         pgpu->compute_class = g->ops.get_litter_value(g, GPU_LIT_COMPUTE_CLASS);