drivers/gpu/drm/ttm/ttm_device.c

   1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
   2
   3 /*
   4  * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
   5  * Copyright 2020 Advanced Micro Devices, Inc.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
  21  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  22  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  23  * OTHER DEALINGS IN THE SOFTWARE.
  24  *
  25  * Authors: Christian König
  26  */
  27
  28 #define pr_fmt(fmt) "[TTM DEVICE] " fmt
  29
  30 #include <linux/debugfs.h>
  31 #include <linux/mm.h>
  32
  33 #include <drm/ttm/ttm_bo.h>
  34 #include <drm/ttm/ttm_device.h>
  35 #include <drm/ttm/ttm_tt.h>
  36 #include <drm/ttm/ttm_placement.h>
  37
  38 #include "ttm_module.h"
  39
  40 /*
  41  * ttm_global_mutex - protecting the global state
  42  */
  43 static DEFINE_MUTEX(ttm_global_mutex);
  44 static unsigned ttm_glob_use_count;
  45 struct ttm_global ttm_glob;
  46 EXPORT_SYMBOL(ttm_glob);
  47
  48 struct dentry *ttm_debugfs_root;
  49
  50 static void ttm_global_release(void)
  51 {
  52         struct ttm_global *glob = &ttm_glob;
  53
  54         mutex_lock(&ttm_global_mutex);
  55         if (--ttm_glob_use_count > 0)
  56                 goto out;
  57
  58         ttm_pool_mgr_fini();
  59         debugfs_remove(ttm_debugfs_root);
  60
  61         __free_page(glob->dummy_read_page);
  62         memset(glob, 0, sizeof(*glob));
  63 out:
  64         mutex_unlock(&ttm_global_mutex);
  65 }
  66
  67 static int ttm_global_init(void)
  68 {
  69         struct ttm_global *glob = &ttm_glob;
  70         unsigned long num_pages, num_dma32;
  71         struct sysinfo si;
  72         int ret = 0;
  73
  74         mutex_lock(&ttm_global_mutex);
  75         if (++ttm_glob_use_count > 1)
  76                 goto out;
  77
  78         si_meminfo(&si);
  79
  80         ttm_debugfs_root = debugfs_create_dir("ttm", NULL);
  81         if (IS_ERR(ttm_debugfs_root)) {
  82                 ttm_debugfs_root = NULL;
  83         }
  84
  85         /* Limit the number of pages in the pool to about 50% of the total
  86          * system memory.
  87          */
  88         num_pages = ((u64)si.totalram * si.mem_unit) >> PAGE_SHIFT;
  89         num_pages /= 2;
  90
  91         /* But for DMA32 we limit ourself to only use 2GiB maximum. */
  92         num_dma32 = (u64)(si.totalram - si.totalhigh) * si.mem_unit
  93                 >> PAGE_SHIFT;
  94         num_dma32 = min(num_dma32, 2UL << (30 - PAGE_SHIFT));
  95
  96         ttm_pool_mgr_init(num_pages);
  97         ttm_tt_mgr_init(num_pages, num_dma32);
  98
  99         glob->dummy_read_page = alloc_page(__GFP_ZERO | GFP_DMA32 |
 100                                            __GFP_NOWARN);
 101
 102         /* Retry without GFP_DMA32 for platforms DMA32 is not available */
 103         if (unlikely(glob->dummy_read_page == NULL)) {
 104                 glob->dummy_read_page = alloc_page(__GFP_ZERO);
 105                 if (unlikely(glob->dummy_read_page == NULL)) {
 106                         ret = -ENOMEM;
 107                         goto out;
 108                 }
 109                 pr_warn("Using GFP_DMA32 fallback for dummy_read_page\n");
 110         }
 111
 112         INIT_LIST_HEAD(&glob->device_list);
 113         atomic_set(&glob->bo_count, 0);
 114
 115         debugfs_create_atomic_t("buffer_objects", 0444, ttm_debugfs_root,
 116                                 &glob->bo_count);
 117 out:
 118         if (ret && ttm_debugfs_root)
 119                 debugfs_remove(ttm_debugfs_root);
 120         if (ret)
 121                 --ttm_glob_use_count;
 122         mutex_unlock(&ttm_global_mutex);
 123         return ret;
 124 }
 125
 126 /*
 127  * A buffer object shrink method that tries to swap out the first
 128  * buffer object on the global::swap_lru list.
 129  */
 130 int ttm_global_swapout(struct ttm_operation_ctx *ctx, gfp_t gfp_flags)
 131 {
 132         struct ttm_global *glob = &ttm_glob;
 133         struct ttm_device *bdev;
 134         int ret = 0;
 135
 136         mutex_lock(&ttm_global_mutex);
 137         list_for_each_entry(bdev, &glob->device_list, device_list) {
 138                 ret = ttm_device_swapout(bdev, ctx, gfp_flags);
 139                 if (ret > 0) {
 140                         list_move_tail(&bdev->device_list, &glob->device_list);
 141                         break;
 142                 }
 143         }
 144         mutex_unlock(&ttm_global_mutex);
 145         return ret;
 146 }
 147
 148 int ttm_device_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,
 149                        gfp_t gfp_flags)
 150 {
 151         struct ttm_resource_cursor cursor;
 152         struct ttm_resource_manager *man;
 153         struct ttm_resource *res;
 154         unsigned i;
 155         int ret;
 156
 157         spin_lock(&bdev->lru_lock);
 158         for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
 159                 man = ttm_manager_type(bdev, i);
 160                 if (!man || !man->use_tt)
 161                         continue;
 162
 163                 ttm_resource_manager_for_each_res(man, &cursor, res) {
 164                         struct ttm_buffer_object *bo = res->bo;
 165                         uint32_t num_pages;
 166
 167                         if (!bo || bo->resource != res)
 168                                 continue;
 169
 170                         num_pages = PFN_UP(bo->base.size);
 171                         ret = ttm_bo_swapout(bo, ctx, gfp_flags);
 172                         /* ttm_bo_swapout has dropped the lru_lock */
 173                         if (!ret)
 174                                 return num_pages;
 175                         if (ret != -EBUSY)
 176                                 return ret;
 177                 }
 178         }
 179         spin_unlock(&bdev->lru_lock);
 180         return 0;
 181 }
 182 EXPORT_SYMBOL(ttm_device_swapout);
 183
 184 /**
 185  * ttm_device_init
 186  *
 187  * @bdev: A pointer to a struct ttm_device to initialize.
 188  * @funcs: Function table for the device.
 189  * @dev: The core kernel device pointer for DMA mappings and allocations.
 190  * @mapping: The address space to use for this bo.
 191  * @vma_manager: A pointer to a vma manager.
 192  * @use_dma_alloc: If coherent DMA allocation API should be used.
 193  * @use_dma32: If we should use GFP_DMA32 for device memory allocations.
 194  *
 195  * Initializes a struct ttm_device:
 196  * Returns:
 197  * !0: Failure.
 198  */
 199 int ttm_device_init(struct ttm_device *bdev, const struct ttm_device_funcs *funcs,
 200                     struct device *dev, struct address_space *mapping,
 201                     struct drm_vma_offset_manager *vma_manager,
 202                     bool use_dma_alloc, bool use_dma32)
 203 {
 204         struct ttm_global *glob = &ttm_glob;
 205         int ret, nid;
 206
 207         if (WARN_ON(vma_manager == NULL))
 208                 return -EINVAL;
 209
 210         ret = ttm_global_init();
 211         if (ret)
 212                 return ret;
 213
 214         bdev->wq = alloc_workqueue("ttm",
 215                                    WQ_MEM_RECLAIM | WQ_HIGHPRI | WQ_UNBOUND, 16);
 216         if (!bdev->wq) {
 217                 ttm_global_release();
 218                 return -ENOMEM;
 219         }
 220
 221         bdev->funcs = funcs;
 222
 223         ttm_sys_man_init(bdev);
 224
 225         if (dev)
 226                 nid = dev_to_node(dev);
 227         else
 228                 nid = NUMA_NO_NODE;
 229
 230         ttm_pool_init(&bdev->pool, dev, nid, use_dma_alloc, use_dma32);
 231
 232         bdev->vma_manager = vma_manager;
 233         spin_lock_init(&bdev->lru_lock);
 234         INIT_LIST_HEAD(&bdev->pinned);
 235         bdev->dev_mapping = mapping;
 236         mutex_lock(&ttm_global_mutex);
 237         list_add_tail(&bdev->device_list, &glob->device_list);
 238         mutex_unlock(&ttm_global_mutex);
 239
 240         return 0;
 241 }
 242 EXPORT_SYMBOL(ttm_device_init);
 243
 244 void ttm_device_fini(struct ttm_device *bdev)
 245 {
 246         struct ttm_resource_manager *man;
 247         unsigned i;
 248
 249         mutex_lock(&ttm_global_mutex);
 250         list_del(&bdev->device_list);
 251         mutex_unlock(&ttm_global_mutex);
 252
 253         drain_workqueue(bdev->wq);
 254         destroy_workqueue(bdev->wq);
 255
 256         man = ttm_manager_type(bdev, TTM_PL_SYSTEM);
 257         ttm_resource_manager_set_used(man, false);
 258         ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, NULL);
 259
 260         spin_lock(&bdev->lru_lock);
 261         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
 262                 if (list_empty(&man->lru[0]))
 263                         pr_debug("Swap list %d was clean\n", i);
 264         spin_unlock(&bdev->lru_lock);
 265
 266         ttm_pool_fini(&bdev->pool);
 267         ttm_global_release();
 268 }
 269 EXPORT_SYMBOL(ttm_device_fini);
 270
 271 static void ttm_device_clear_lru_dma_mappings(struct ttm_device *bdev,
 272                                               struct list_head *list)
 273 {
 274         struct ttm_resource *res;
 275
 276         spin_lock(&bdev->lru_lock);
 277         while ((res = list_first_entry_or_null(list, typeof(*res), lru))) {
 278                 struct ttm_buffer_object *bo = res->bo;
 279
 280                 /* Take ref against racing releases once lru_lock is unlocked */
 281                 if (!ttm_bo_get_unless_zero(bo))
 282                         continue;
 283
 284                 list_del_init(&res->lru);
 285                 spin_unlock(&bdev->lru_lock);
 286
 287                 if (bo->ttm)
 288                         ttm_tt_unpopulate(bo->bdev, bo->ttm);
 289
 290                 ttm_bo_put(bo);
 291                 spin_lock(&bdev->lru_lock);
 292         }
 293         spin_unlock(&bdev->lru_lock);
 294 }
 295
 296 void ttm_device_clear_dma_mappings(struct ttm_device *bdev)
 297 {
 298         struct ttm_resource_manager *man;
 299         unsigned int i, j;
 300
 301         ttm_device_clear_lru_dma_mappings(bdev, &bdev->pinned);
 302
 303         for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
 304                 man = ttm_manager_type(bdev, i);
 305                 if (!man || !man->use_tt)
 306                         continue;
 307
 308                 for (j = 0; j < TTM_MAX_BO_PRIORITY; ++j)
 309                         ttm_device_clear_lru_dma_mappings(bdev, &man->lru[j]);
 310         }
 311 }
 312 EXPORT_SYMBOL(ttm_device_clear_dma_mappings);