drm: GEM mmap support

Add core support for mapping of GEM objects.  Drivers should provide a
vm_operations_struct if they want to support page faulting of objects.
The code for handling GEM object offsets was taken from TTM, which was
written by Thomas Hellström.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>

2 files changed, 22 insertions, 0 deletions

diff --git a/include/drm/drm.h b/include/drm/drm.h
index 3fb173c5af3e..3a66252456ba 100644
--- a/include/drm/drm.h
+++ b/include/drm/drm.h
@@ -173,6 +173,7 @@ enum drm_map_type {
         _DRM_AGP = 3,             /**< AGP/GART */
         _DRM_SCATTER_GATHER = 4,  /**< Scatter/gather memory for PCI DMA */
         _DRM_CONSISTENT = 5,      /**< Consistent memory for PCI DMA */
+        _DRM_GEM = 6,             /**< GEM object */
 };
 
 /**
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index c9cc618dbcfc..ae42a6a5c24e 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -528,6 +528,7 @@ struct drm_map_list {
         struct drm_map *map;                    /**< mapping */
         uint64_t user_token;
         struct drm_master *master;
+        struct drm_mm_node *file_offset_node;   /**< fake offset */
 };
 
 typedef struct drm_map drm_local_map_t;
@@ -568,6 +569,14 @@ struct drm_ati_pcigart_info {
 };
 
 /**
+ * GEM specific mm private for tracking GEM objects
+ */
+struct drm_gem_mm {
+        struct drm_mm offset_manager;   /**< Offset mgmt for buffer objects */
+        struct drm_open_hash offset_hash; /**< User token hash table for maps */
+};
+
+/**
  * This structure defines the drm_mm memory object, which will be used by the
  * DRM for its buffer objects.
  */
@@ -584,6 +593,9 @@ struct drm_gem_object {
         /** File representing the shmem storage */
         struct file *filp;
 
+        /* Mapping info for this object */
+        struct drm_map_list map_list;
+
         /**
          * Size of the object, in bytes.  Immutable over the object's
          * lifetime.
@@ -758,6 +770,9 @@ struct drm_driver {
         int (*gem_init_object) (struct drm_gem_object *obj);
         void (*gem_free_object) (struct drm_gem_object *obj);
 
+        /* Driver private ops for this object */
+        struct vm_operations_struct *gem_vm_ops;
+
         int major;
         int minor;
         int patchlevel;
@@ -910,6 +925,8 @@ struct drm_device {
         struct drm_sg_mem *sg;  /**< Scatter gather memory */
         int num_crtcs;                  /**< Number of CRTCs on this device */
         void *dev_private;              /**< device private data */
+        void *mm_private;
+        struct address_space *dev_mapping;
         struct drm_sigdata sigdata;        /**< For block_all_signals */
         sigset_t sigmask;
 
@@ -1026,6 +1043,8 @@ extern int drm_release(struct inode *inode, struct file *filp);
 
                                 /* Mapping support (drm_vm.h) */
 extern int drm_mmap(struct file *filp, struct vm_area_struct *vma);
+extern int drm_mmap_locked(struct file *filp, struct vm_area_struct *vma);
+extern void drm_vm_open_locked(struct vm_area_struct *vma);
 extern unsigned long drm_core_get_map_ofs(struct drm_map * map);
 extern unsigned long drm_core_get_reg_ofs(struct drm_device *dev);
 extern unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait);
@@ -1287,10 +1306,12 @@ extern int drm_mm_add_space_to_tail(struct drm_mm *mm, unsigned long size);
 
 /* Graphics Execution Manager library functions (drm_gem.c) */
 int drm_gem_init(struct drm_device *dev);
+void drm_gem_destroy(struct drm_device *dev);
 void drm_gem_object_free(struct kref *kref);
 struct drm_gem_object *drm_gem_object_alloc(struct drm_device *dev,
                                             size_t size);
 void drm_gem_object_handle_free(struct kref *kref);
+int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma);
 
 static inline void
 drm_gem_object_reference(struct drm_gem_object *obj)