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/mm.h>
  31
  32 #include <drm/ttm/ttm_bo.h>
  33 #include <drm/ttm/ttm_device.h>
  34 #include <drm/ttm/ttm_tt.h>
  35 #include <drm/ttm/ttm_placement.h>
  36
  37 #include "ttm_module.h"
  38
  39 /*
  40  * ttm_global_mutex - protecting the global state
  41  */
  42 static DEFINE_MUTEX(ttm_global_mutex);
  43 static unsigned ttm_glob_use_count;
  44 struct ttm_global ttm_glob;
  45 EXPORT_SYMBOL(ttm_glob);
  46
  47 struct dentry *ttm_debugfs_root;
  48
  49 static void ttm_global_release(void)
  50 {
  51         struct ttm_global *glob = &ttm_glob;
  52
  53         mutex_lock(&ttm_global_mutex);
  54         if (--ttm_glob_use_count > 0)
  55                 goto out;
  56
  57         ttm_pool_mgr_fini();
  58         debugfs_remove(ttm_debugfs_root);
  59
  60         __free_page(glob->dummy_read_page);
  61         memset(glob, 0, sizeof(*glob));
  62 out:
  63         mutex_unlock(&ttm_global_mutex);
  64 }
  65
  66 static int ttm_global_init(void)
  67 {
  68         struct ttm_global *glob = &ttm_glob;
  69         unsigned long num_pages, num_dma32;
  70         struct sysinfo si;
  71         int ret = 0;
  72
  73         mutex_lock(&ttm_global_mutex);
  74         if (++ttm_glob_use_count > 1)
  75                 goto out;
  76
  77         si_meminfo(&si);
  78
  79         ttm_debugfs_root = debugfs_create_dir("ttm", NULL);
  80         if (IS_ERR(ttm_debugfs_root)) {
  81                 ttm_debugfs_root = NULL;
  82         }
  83
  84         /* Limit the number of pages in the pool to about 50% of the total
  85          * system memory.
  86          */
  87         num_pages = ((u64)si.totalram * si.mem_unit) >> PAGE_SHIFT;
  88         num_pages /= 2;
  89
  90         /* But for DMA32 we limit ourself to only use 2GiB maximum. */
  91         num_dma32 = (u64)(si.totalram - si.totalhigh) * si.mem_unit
  92                 >> PAGE_SHIFT;
  93         num_dma32 = min(num_dma32, 2UL << (30 - PAGE_SHIFT));
  94
  95         ttm_pool_mgr_init(num_pages);
  96         ttm_tt_mgr_init(num_pages, num_dma32);
  97
  98         glob->dummy_read_page = alloc_page(__GFP_ZERO | GFP_DMA32 |
  99                                            __GFP_NOWARN);
 100
 101         /* Retry without GFP_DMA32 for platforms DMA32 is not available */
 102         if (unlikely(glob->dummy_read_page == NULL)) {
 103                 glob->dummy_read_page = alloc_page(__GFP_ZERO);
 104                 if (unlikely(glob->dummy_read_page == NULL)) {
 105                         ret = -ENOMEM;
 106                         goto out;
 107                 }
 108                 pr_warn("Using GFP_DMA32 fallback for dummy_read_page\n");
 109         }
 110
 111         INIT_LIST_HEAD(&glob->device_list);
 112         atomic_set(&glob->bo_count, 0);
 113
 114         debugfs_create_atomic_t("buffer_objects", 0444, ttm_debugfs_root,
 115                                 &glob->bo_count);
 116 out:
 117         if (ret && ttm_debugfs_root)
 118                 debugfs_remove(ttm_debugfs_root);
 119         if (ret)
 120                 --ttm_glob_use_count;
 121         mutex_unlock(&ttm_global_mutex);
 122         return ret;
 123 }
 124
 125 /*
 126  * A buffer object shrink method that tries to swap out the first
 127  * buffer object on the global::swap_lru list.
 128  */
 129 int ttm_global_swapout(struct ttm_operation_ctx *ctx, gfp_t gfp_flags)
 130 {
 131         struct ttm_global *glob = &ttm_glob;
 132         struct ttm_device *bdev;
 133         int ret = 0;
 134
 135         mutex_lock(&ttm_global_mutex);
 136         list_for_each_entry(bdev, &glob->device_list, device_list) {
 137                 ret = ttm_device_swapout(bdev, ctx, gfp_flags);
 138                 if (ret > 0) {
 139                         list_move_tail(&bdev->device_list, &glob->device_list);
 140                         break;
 141                 }
 142         }
 143         mutex_unlock(&ttm_global_mutex);
 144         return ret;
 145 }
 146
 147 int ttm_device_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,
 148                        gfp_t gfp_flags)
 149 {
 150         struct ttm_resource_cursor cursor;
 151         struct ttm_resource_manager *man;
 152         struct ttm_resource *res;
 153         unsigned i;
 154         int ret;
 155
 156         spin_lock(&bdev->lru_lock);
 157         for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
 158                 man = ttm_manager_type(bdev, i);
 159                 if (!man || !man->use_tt)
 160                         continue;
 161
 162                 ttm_resource_manager_for_each_res(man, &cursor, res) {
 163                         struct ttm_buffer_object *bo = res->bo;
 164                         uint32_t num_pages;
 165
 166                         if (!bo || bo->resource != res)
 167                                 continue;
 168
 169                         num_pages = PFN_UP(bo->base.size);
 170                         ret = ttm_bo_swapout(bo, ctx, gfp_flags);
 171                         /* ttm_bo_swapout has dropped the lru_lock */
 172                         if (!ret)
 173                                 return num_pages;
 174                         if (ret != -EBUSY)
 175                                 return ret;
 176                 }
 177         }
 178         spin_unlock(&bdev->lru_lock);
 179         return 0;
 180 }
 181 EXPORT_SYMBOL(ttm_device_swapout);
 182
 183 /**
 184  * ttm_device_init
 185  *
 186  * @bdev: A pointer to a struct ttm_device to initialize.
 187  * @funcs: Function table for the device.
 188  * @dev: The core kernel device pointer for DMA mappings and allocations.
 189  * @mapping: The address space to use for this bo.
 190  * @vma_manager: A pointer to a vma manager.
 191  * @use_dma_alloc: If coherent DMA allocation API should be used.
 192  * @use_dma32: If we should use GFP_DMA32 for device memory allocations.
 193  *
 194  * Initializes a struct ttm_device:
 195  * Returns:
 196  * !0: Failure.
 197  */
 198 int ttm_device_init(struct ttm_device *bdev, const struct ttm_device_funcs *funcs,
 199                     struct device *dev, struct address_space *mapping,
 200                     struct drm_vma_offset_manager *vma_manager,
 201                     bool use_dma_alloc, bool use_dma32)
 202 {
 203         struct ttm_global *glob = &ttm_glob;
 204         int ret;
 205
 206         if (WARN_ON(vma_manager == NULL))
 207                 return -EINVAL;
 208
 209         ret = ttm_global_init();
 210         if (ret)
 211                 return ret;
 212
 213         bdev->wq = alloc_workqueue("ttm",
 214                                    WQ_MEM_RECLAIM | WQ_HIGHPRI | WQ_UNBOUND, 16);
 215         if (!bdev->wq) {
 216                 ttm_global_release();
 217                 return -ENOMEM;
 218         }
 219
 220         bdev->funcs = funcs;
 221
 222         ttm_sys_man_init(bdev);
 223
 224         ttm_pool_init(&bdev->pool, dev, dev_to_node(dev), use_dma_alloc, use_dma32);
 225
 226         bdev->vma_manager = vma_manager;
 227         spin_lock_init(&bdev->lru_lock);
 228         INIT_LIST_HEAD(&bdev->pinned);
 229         bdev->dev_mapping = mapping;
 230         mutex_lock(&ttm_global_mutex);
 231         list_add_tail(&bdev->device_list, &glob->device_list);
 232         mutex_unlock(&ttm_global_mutex);
 233
 234         return 0;
 235 }
 236 EXPORT_SYMBOL(ttm_device_init);
 237
 238 void ttm_device_fini(struct ttm_device *bdev)
 239 {
 240         struct ttm_resource_manager *man;
 241         unsigned i;
 242
 243         mutex_lock(&ttm_global_mutex);
 244         list_del(&bdev->device_list);
 245         mutex_unlock(&ttm_global_mutex);
 246
 247         drain_workqueue(bdev->wq);
 248         destroy_workqueue(bdev->wq);
 249
 250         man = ttm_manager_type(bdev, TTM_PL_SYSTEM);
 251         ttm_resource_manager_set_used(man, false);
 252         ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, NULL);
 253
 254         spin_lock(&bdev->lru_lock);
 255         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
 256                 if (list_empty(&man->lru[0]))
 257                         pr_debug("Swap list %d was clean\n", i);
 258         spin_unlock(&bdev->lru_lock);
 259
 260         ttm_pool_fini(&bdev->pool);
 261         ttm_global_release();
 262 }
 263 EXPORT_SYMBOL(ttm_device_fini);
 264
 265 static void ttm_device_clear_lru_dma_mappings(struct ttm_device *bdev,
 266                                               struct list_head *list)
 267 {
 268         struct ttm_resource *res;
 269
 270         spin_lock(&bdev->lru_lock);
 271         while ((res = list_first_entry_or_null(list, typeof(*res), lru))) {
 272                 struct ttm_buffer_object *bo = res->bo;
 273
 274                 /* Take ref against racing releases once lru_lock is unlocked */
 275                 if (!ttm_bo_get_unless_zero(bo))
 276                         continue;
 277
 278                 list_del_init(&res->lru);
 279                 spin_unlock(&bdev->lru_lock);
 280
 281                 if (bo->ttm)
 282                         ttm_tt_unpopulate(bo->bdev, bo->ttm);
 283
 284                 ttm_bo_put(bo);
 285                 spin_lock(&bdev->lru_lock);
 286         }
 287         spin_unlock(&bdev->lru_lock);
 288 }
 289
 290 void ttm_device_clear_dma_mappings(struct ttm_device *bdev)
 291 {
 292         struct ttm_resource_manager *man;
 293         unsigned int i, j;
 294
 295         ttm_device_clear_lru_dma_mappings(bdev, &bdev->pinned);
 296
 297         for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
 298                 man = ttm_manager_type(bdev, i);
 299                 if (!man || !man->use_tt)
 300                         continue;
 301
 302                 for (j = 0; j < TTM_MAX_BO_PRIORITY; ++j)
 303                         ttm_device_clear_lru_dma_mappings(bdev, &man->lru[j]);
 304         }
 305 }
 306 EXPORT_SYMBOL(ttm_device_clear_dma_mappings);