drivers/gpu/drm/vmwgfx/vmwgfx_gmrid_manager.c

   1 /**************************************************************************
   2  *
   3  * Copyright (c) 2007-2010 VMware, Inc., Palo Alto, CA., USA
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  21  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  22  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  23  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  24  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27 /*
  28  * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
  29  */
  30
  31 #include "vmwgfx_drv.h"
  32 #include "ttm/ttm_module.h"
  33 #include "ttm/ttm_bo_driver.h"
  34 #include "ttm/ttm_placement.h"
  35 #include <linux/idr.h>
  36 #include <linux/spinlock.h>
  37 #include <linux/kernel.h>
  38
  39 struct vmwgfx_gmrid_man {
  40         spinlock_t lock;
  41         struct ida gmr_ida;
  42         uint32_t max_gmr_ids;
  43 };
  44
  45 static int vmw_gmrid_man_get_node(struct ttm_mem_type_manager *man,
  46                                   struct ttm_buffer_object *bo,
  47                                   struct ttm_placement *placement,
  48                                   struct ttm_mem_reg *mem)
  49 {
  50         struct vmwgfx_gmrid_man *gman =
  51                 (struct vmwgfx_gmrid_man *)man->priv;
  52         int ret;
  53         int id;
  54
  55         mem->mm_node = NULL;
  56
  57         do {
  58                 if (unlikely(ida_pre_get(&gman->gmr_ida, GFP_KERNEL) == 0))
  59                         return -ENOMEM;
  60
  61                 spin_lock(&gman->lock);
  62                 ret = ida_get_new(&gman->gmr_ida, &id);
  63
  64                 if (unlikely(ret == 0 && id >= gman->max_gmr_ids)) {
  65                         ida_remove(&gman->gmr_ida, id);
  66                         spin_unlock(&gman->lock);
  67                         return 0;
  68                 }
  69
  70                 spin_unlock(&gman->lock);
  71
  72         } while (ret == -EAGAIN);
  73
  74         if (likely(ret == 0)) {
  75                 mem->mm_node = gman;
  76                 mem->start = id;
  77         }
  78
  79         return ret;
  80 }
  81
  82 static void vmw_gmrid_man_put_node(struct ttm_mem_type_manager *man,
  83                                    struct ttm_mem_reg *mem)
  84 {
  85         struct vmwgfx_gmrid_man *gman =
  86                 (struct vmwgfx_gmrid_man *)man->priv;
  87
  88         if (mem->mm_node) {
  89                 spin_lock(&gman->lock);
  90                 ida_remove(&gman->gmr_ida, mem->start);
  91                 spin_unlock(&gman->lock);
  92                 mem->mm_node = NULL;
  93         }
  94 }
  95
  96 static int vmw_gmrid_man_init(struct ttm_mem_type_manager *man,
  97                               unsigned long p_size)
  98 {
  99         struct vmwgfx_gmrid_man *gman =
 100                 kzalloc(sizeof(*gman), GFP_KERNEL);
 101
 102         if (unlikely(gman == NULL))
 103                 return -ENOMEM;
 104
 105         spin_lock_init(&gman->lock);
 106         ida_init(&gman->gmr_ida);
 107         gman->max_gmr_ids = p_size;
 108         man->priv = (void *) gman;
 109         return 0;
 110 }
 111
 112 static int vmw_gmrid_man_takedown(struct ttm_mem_type_manager *man)
 113 {
 114         struct vmwgfx_gmrid_man *gman =
 115                 (struct vmwgfx_gmrid_man *)man->priv;
 116
 117         if (gman) {
 118                 ida_destroy(&gman->gmr_ida);
 119                 kfree(gman);
 120         }
 121         return 0;
 122 }
 123
 124 static void vmw_gmrid_man_debug(struct ttm_mem_type_manager *man,
 125                                 const char *prefix)
 126 {
 127         printk(KERN_INFO "%s: No debug info available for the GMR "
 128                "id manager.\n", prefix);
 129 }
 130
 131 const struct ttm_mem_type_manager_func vmw_gmrid_manager_func = {
 132         vmw_gmrid_man_init,
 133         vmw_gmrid_man_takedown,
 134         vmw_gmrid_man_get_node,
 135         vmw_gmrid_man_put_node,
 136         vmw_gmrid_man_debug
 137 };