ttm: Make parts of a struct ttm_bo_device global.

Common resources, like memory accounting and swap lists should be
global and not per device. Introduce a struct ttm_bo_global to
accomodate this, and register it with sysfs. Add a small sysfs interface
to return the number of active buffer objects.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>

drivers/gpu/drm/radeon/radeon_object.h

@@ -37,6 +37,7 @@
  * TTM.
  */
 struct radeon_mman {
+	struct ttm_bo_global_ref        bo_global_ref;
 	struct ttm_global_reference	mem_global_ref;
 	bool				mem_global_referenced;
 	struct ttm_bo_device		bdev;

drivers/gpu/drm/radeon/radeon_ttm.c

@@ -77,9 +77,25 @@ static int radeon_ttm_global_init(struct radeon_device *rdev)
 	global_ref->release = &radeon_ttm_mem_global_release;
 	r = ttm_global_item_ref(global_ref);
 	if (r != 0) {
-		DRM_ERROR("Failed referencing a global TTM memory object.\n");
+		DRM_ERROR("Failed setting up TTM memory accounting "
+			  "subsystem.\n");
 		return r;
 	}
+
+	rdev->mman.bo_global_ref.mem_glob =
+		rdev->mman.mem_global_ref.object;
+	global_ref = &rdev->mman.bo_global_ref.ref;
+	global_ref->global_type = TTM_GLOBAL_TTM_BO;
+	global_ref->size = sizeof(struct ttm_mem_global);
+	global_ref->init = &ttm_bo_global_init;
+	global_ref->release = &ttm_bo_global_release;
+	r = ttm_global_item_ref(global_ref);
+	if (r != 0) {
+		DRM_ERROR("Failed setting up TTM BO subsystem.\n");
+		ttm_global_item_unref(&rdev->mman.mem_global_ref);
+		return r;
+	}
+
 	rdev->mman.mem_global_referenced = true;
 	return 0;
 }
@@ -87,6 +103,7 @@ static int radeon_ttm_global_init(struct radeon_device *rdev)
 static void radeon_ttm_global_fini(struct radeon_device *rdev)
 {
 	if (rdev->mman.mem_global_referenced) {
+		ttm_global_item_unref(&rdev->mman.bo_global_ref.ref);
 		ttm_global_item_unref(&rdev->mman.mem_global_ref);
 		rdev->mman.mem_global_referenced = false;
 	}
@@ -286,9 +303,11 @@ static int radeon_move_vram_ram(struct ttm_buffer_object *bo,
 	r = ttm_bo_move_ttm(bo, true, no_wait, new_mem);
 out_cleanup:
 	if (tmp_mem.mm_node) {
-		spin_lock(&rdev->mman.bdev.lru_lock);
+		struct ttm_bo_global *glob = rdev->mman.bdev.glob;
+
+		spin_lock(&glob->lru_lock);
 		drm_mm_put_block(tmp_mem.mm_node);
-		spin_unlock(&rdev->mman.bdev.lru_lock);
+		spin_unlock(&glob->lru_lock);
 		return r;
 	}
 	return r;
@@ -323,9 +342,11 @@ static int radeon_move_ram_vram(struct ttm_buffer_object *bo,
 	}
 out_cleanup:
 	if (tmp_mem.mm_node) {
-		spin_lock(&rdev->mman.bdev.lru_lock);
+		struct ttm_bo_global *glob = rdev->mman.bdev.glob;
+
+		spin_lock(&glob->lru_lock);
 		drm_mm_put_block(tmp_mem.mm_node);
-		spin_unlock(&rdev->mman.bdev.lru_lock);
+		spin_unlock(&glob->lru_lock);
 		return r;
 	}
 	return r;
@@ -441,7 +462,7 @@ int radeon_ttm_init(struct radeon_device *rdev)
 	}
 	/* No others user of address space so set it to 0 */
 	r = ttm_bo_device_init(&rdev->mman.bdev,
-			       rdev->mman.mem_global_ref.object,
+			       rdev->mman.bo_global_ref.ref.object,
 			       &radeon_bo_driver, DRM_FILE_PAGE_OFFSET);
 	if (r) {
 		DRM_ERROR("failed initializing buffer object driver(%d).\n", r);

drivers/gpu/drm/ttm/ttm_bo_util.c

@@ -41,9 +41,9 @@ void ttm_bo_free_old_node(struct ttm_buffer_object *bo)
 	struct ttm_mem_reg *old_mem = &bo->mem;
 
 	if (old_mem->mm_node) {
-		spin_lock(&bo->bdev->lru_lock);
+		spin_lock(&bo->glob->lru_lock);
 		drm_mm_put_block(old_mem->mm_node);
-		spin_unlock(&bo->bdev->lru_lock);
+		spin_unlock(&bo->glob->lru_lock);
 	}
 	old_mem->mm_node = NULL;
 }

drivers/gpu/drm/ttm/ttm_tt.c

@@ -166,7 +166,7 @@ static void ttm_tt_free_user_pages(struct ttm_tt *ttm)
 			set_page_dirty_lock(page);
 
 		ttm->pages[i] = NULL;
-		ttm_mem_global_free(ttm->bdev->mem_glob, PAGE_SIZE);
+		ttm_mem_global_free(ttm->glob->mem_glob, PAGE_SIZE);
 		put_page(page);
 	}
 	ttm->state = tt_unpopulated;
@@ -177,8 +177,7 @@ static void ttm_tt_free_user_pages(struct ttm_tt *ttm)
 static struct page *__ttm_tt_get_page(struct ttm_tt *ttm, int index)
 {
 	struct page *p;
-	struct ttm_bo_device *bdev = ttm->bdev;
-	struct ttm_mem_global *mem_glob = bdev->mem_glob;
+	struct ttm_mem_global *mem_glob = ttm->glob->mem_glob;
 	int ret;
 
 	while (NULL == (p = ttm->pages[index])) {
@@ -348,7 +347,7 @@ static void ttm_tt_free_alloced_pages(struct ttm_tt *ttm)
 				printk(KERN_ERR TTM_PFX
 				       "Erroneous page count. "
 				       "Leaking pages.\n");
-			ttm_mem_global_free_page(ttm->bdev->mem_glob,
+			ttm_mem_global_free_page(ttm->glob->mem_glob,
 						 cur_page);
 			__free_page(cur_page);
 		}
@@ -394,7 +393,7 @@ int ttm_tt_set_user(struct ttm_tt *ttm,
 	struct mm_struct *mm = tsk->mm;
 	int ret;
 	int write = (ttm->page_flags & TTM_PAGE_FLAG_WRITE) != 0;
-	struct ttm_mem_global *mem_glob = ttm->bdev->mem_glob;
+	struct ttm_mem_global *mem_glob = ttm->glob->mem_glob;
 
 	BUG_ON(num_pages != ttm->num_pages);
 	BUG_ON((ttm->page_flags & TTM_PAGE_FLAG_USER) == 0);
@@ -439,8 +438,7 @@ struct ttm_tt *ttm_tt_create(struct ttm_bo_device *bdev, unsigned long size,
 	if (!ttm)
 		return NULL;
 
-	ttm->bdev = bdev;
-
+	ttm->glob = bdev->glob;
 	ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
 	ttm->first_himem_page = ttm->num_pages;
 	ttm->last_lomem_page = -1;

include/drm/ttm/ttm_bo_api.h

@@ -155,6 +155,7 @@ struct ttm_buffer_object {
 	 * Members constant at init.
 	 */
 
+	struct ttm_bo_global *glob;
 	struct ttm_bo_device *bdev;
 	unsigned long buffer_start;
 	enum ttm_bo_type type;

include/drm/ttm/ttm_bo_driver.h

@@ -32,6 +32,7 @@
 
 #include "ttm/ttm_bo_api.h"
 #include "ttm/ttm_memory.h"
+#include "ttm/ttm_module.h"
 #include "drm_mm.h"
 #include "linux/workqueue.h"
 #include "linux/fs.h"
@@ -160,7 +161,7 @@ struct ttm_tt {
 	long last_lomem_page;
 	uint32_t page_flags;
 	unsigned long num_pages;
-	struct ttm_bo_device *bdev;
+	struct ttm_bo_global *glob;
 	struct ttm_backend *be;
 	struct task_struct *tsk;
 	unsigned long start;
@@ -355,24 +356,73 @@ struct ttm_bo_driver {
 	void *(*sync_obj_ref) (void *sync_obj);
 };
 
-#define TTM_NUM_MEM_TYPES 8
+/**
+ * struct ttm_bo_global_ref - Argument to initialize a struct ttm_bo_global.
+ */
+
+struct ttm_bo_global_ref {
+	struct ttm_global_reference ref;
+	struct ttm_mem_global *mem_glob;
+};
 
-#define TTM_BO_PRIV_FLAG_MOVING  0	/* Buffer object is moving and needs
-					   idling before CPU mapping */
-#define TTM_BO_PRIV_FLAG_MAX 1
 /**
- * struct ttm_bo_device - Buffer object driver device-specific data.
+ * struct ttm_bo_global - Buffer object driver global data.
  *
  * @mem_glob: Pointer to a struct ttm_mem_global object for accounting.
- * @driver: Pointer to a struct ttm_bo_driver struct setup by the driver.
- * @count: Current number of buffer object.
- * @pages: Current number of pinned pages.
  * @dummy_read_page: Pointer to a dummy page used for mapping requests
  * of unpopulated pages.
- * @shrink: A shrink callback object used for buffre object swap.
+ * @shrink: A shrink callback object used for buffer object swap.
  * @ttm_bo_extra_size: Extra size (sizeof(struct ttm_buffer_object) excluded)
  * used by a buffer object. This is excluding page arrays and backing pages.
  * @ttm_bo_size: This is @ttm_bo_extra_size + sizeof(struct ttm_buffer_object).
+ * @device_list_mutex: Mutex protecting the device list.
+ * This mutex is held while traversing the device list for pm options.
+ * @lru_lock: Spinlock protecting the bo subsystem lru lists.
+ * @device_list: List of buffer object devices.
+ * @swap_lru: Lru list of buffer objects used for swapping.
+ */
+
+struct ttm_bo_global {
+
+	/**
+	 * Constant after init.
+	 */
+
+	struct kobject kobj;
+	struct ttm_mem_global *mem_glob;
+	struct page *dummy_read_page;
+	struct ttm_mem_shrink shrink;
+	size_t ttm_bo_extra_size;
+	size_t ttm_bo_size;
+	struct mutex device_list_mutex;
+	spinlock_t lru_lock;
+
+	/**
+	 * Protected by device_list_mutex.
+	 */
+	struct list_head device_list;
+
+	/**
+	 * Protected by the lru_lock.
+	 */
+	struct list_head swap_lru;
+
+	/**
+	 * Internal protection.
+	 */
+	atomic_t bo_count;
+};
+
+
+#define TTM_NUM_MEM_TYPES 8
+
+#define TTM_BO_PRIV_FLAG_MOVING  0	/* Buffer object is moving and needs
+					   idling before CPU mapping */
+#define TTM_BO_PRIV_FLAG_MAX 1
+/**
+ * struct ttm_bo_device - Buffer object driver device-specific data.
+ *
+ * @driver: Pointer to a struct ttm_bo_driver struct setup by the driver.
  * @man: An array of mem_type_managers.
  * @addr_space_mm: Range manager for the device address space.
  * lru_lock: Spinlock that protects the buffer+device lru lists and
@@ -390,32 +440,21 @@ struct ttm_bo_device {
 	/*
 	 * Constant after bo device init / atomic.
 	 */
-
-	struct ttm_mem_global *mem_glob;
+	struct list_head device_list;
+	struct ttm_bo_global *glob;
 	struct ttm_bo_driver *driver;
-	struct page *dummy_read_page;
-	struct ttm_mem_shrink shrink;
-
-	size_t ttm_bo_extra_size;
-	size_t ttm_bo_size;
-
 	rwlock_t vm_lock;
+	struct ttm_mem_type_manager man[TTM_NUM_MEM_TYPES];
 	/*
 	 * Protected by the vm lock.
 	 */
-	struct ttm_mem_type_manager man[TTM_NUM_MEM_TYPES];
 	struct rb_root addr_space_rb;
 	struct drm_mm addr_space_mm;
 
 	/*
-	 * Might want to change this to one lock per manager.
-	 */
-	spinlock_t lru_lock;
-	/*
-	 * Protected by the lru lock.
+	 * Protected by the global:lru lock.
 	 */
 	struct list_head ddestroy;
-	struct list_head swap_lru;
 
 	/*
 	 * Protected by load / firstopen / lastclose /unload sync.
@@ -629,6 +668,9 @@ extern int ttm_bo_pci_offset(struct ttm_bo_device *bdev,
 			     unsigned long *bus_offset,
 			     unsigned long *bus_size);
 
+extern void ttm_bo_global_release(struct ttm_global_reference *ref);
+extern int ttm_bo_global_init(struct ttm_global_reference *ref);
+
 extern int ttm_bo_device_release(struct ttm_bo_device *bdev);
 
 /**
@@ -646,7 +688,7 @@ extern int ttm_bo_device_release(struct ttm_bo_device *bdev);
  * !0: Failure.
  */
 extern int ttm_bo_device_init(struct ttm_bo_device *bdev,
-			      struct ttm_mem_global *mem_glob,
+			      struct ttm_bo_global *glob,
 			      struct ttm_bo_driver *driver,
 			      uint64_t file_page_offset);