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_device.h>
  33 #include <drm/ttm/ttm_tt.h>
  34 #include <drm/ttm/ttm_placement.h>
  35 #include <drm/ttm/ttm_bo_api.h>
  36
  37 #include "ttm_module.h"
  38
  39 /**
  40  * ttm_global_mutex - protecting the global state
  41  */
  42 DEFINE_MUTEX(ttm_global_mutex);
  43 unsigned ttm_glob_use_count;
  44 struct ttm_global ttm_glob;
  45 EXPORT_SYMBOL(ttm_glob);
  46
  47 static void ttm_global_release(void)
  48 {
  49         struct ttm_global *glob = &ttm_glob;
  50
  51         mutex_lock(&ttm_global_mutex);
  52         if (--ttm_glob_use_count > 0)
  53                 goto out;
  54
  55         ttm_pool_mgr_fini();
  56
  57         __free_page(glob->dummy_read_page);
  58         memset(glob, 0, sizeof(*glob));
  59 out:
  60         mutex_unlock(&ttm_global_mutex);
  61 }
  62
  63 static int ttm_global_init(void)
  64 {
  65         struct ttm_global *glob = &ttm_glob;
  66         unsigned long num_pages, num_dma32;
  67         struct sysinfo si;
  68         int ret = 0;
  69
  70         mutex_lock(&ttm_global_mutex);
  71         if (++ttm_glob_use_count > 1)
  72                 goto out;
  73
  74         si_meminfo(&si);
  75
  76         /* Limit the number of pages in the pool to about 50% of the total
  77          * system memory.
  78          */
  79         num_pages = ((u64)si.totalram * si.mem_unit) >> PAGE_SHIFT;
  80         num_pages /= 2;
  81
  82         /* But for DMA32 we limit ourself to only use 2GiB maximum. */
  83         num_dma32 = (u64)(si.totalram - si.totalhigh) * si.mem_unit
  84                 >> PAGE_SHIFT;
  85         num_dma32 = min(num_dma32, 2UL << (30 - PAGE_SHIFT));
  86
  87         ttm_pool_mgr_init(num_pages);
  88         ttm_tt_mgr_init(num_pages, num_dma32);
  89
  90         glob->dummy_read_page = alloc_page(__GFP_ZERO | GFP_DMA32);
  91
  92         if (unlikely(glob->dummy_read_page == NULL)) {
  93                 ret = -ENOMEM;
  94                 goto out;
  95         }
  96
  97         INIT_LIST_HEAD(&glob->device_list);
  98         atomic_set(&glob->bo_count, 0);
  99
 100         debugfs_create_atomic_t("buffer_objects", 0444, ttm_debugfs_root,
 101                                 &glob->bo_count);
 102 out:
 103         mutex_unlock(&ttm_global_mutex);
 104         return ret;
 105 }
 106
 107 /**
 108  * A buffer object shrink method that tries to swap out the first
 109  * buffer object on the global::swap_lru list.
 110  */
 111 int ttm_global_swapout(struct ttm_operation_ctx *ctx, gfp_t gfp_flags)
 112 {
 113         struct ttm_global *glob = &ttm_glob;
 114         struct ttm_device *bdev;
 115         int ret = 0;
 116
 117         mutex_lock(&ttm_global_mutex);
 118         list_for_each_entry(bdev, &glob->device_list, device_list) {
 119                 ret = ttm_device_swapout(bdev, ctx, gfp_flags);
 120                 if (ret > 0) {
 121                         list_move_tail(&bdev->device_list, &glob->device_list);
 122                         break;
 123                 }
 124         }
 125         mutex_unlock(&ttm_global_mutex);
 126         return ret;
 127 }
 128 EXPORT_SYMBOL(ttm_global_swapout);
 129
 130 int ttm_device_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,
 131                        gfp_t gfp_flags)
 132 {
 133         struct ttm_resource_manager *man;
 134         struct ttm_buffer_object *bo;
 135         unsigned i, j;
 136         int ret;
 137
 138         spin_lock(&bdev->lru_lock);
 139         for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
 140                 man = ttm_manager_type(bdev, i);
 141                 if (!man || !man->use_tt)
 142                         continue;
 143
 144                 for (j = 0; j < TTM_MAX_BO_PRIORITY; ++j) {
 145                         list_for_each_entry(bo, &man->lru[j], lru) {
 146                                 uint32_t num_pages;
 147
 148                                 if (!bo->ttm || !ttm_tt_is_populated(bo->ttm) ||
 149                                     bo->ttm->page_flags & TTM_PAGE_FLAG_SG ||
 150                                     bo->ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)
 151                                         continue;
 152
 153                                 num_pages = bo->ttm->num_pages;
 154                                 ret = ttm_bo_swapout(bo, ctx, gfp_flags);
 155                                 /* ttm_bo_swapout has dropped the lru_lock */
 156                                 if (!ret)
 157                                         return num_pages;
 158                                 if (ret != -EBUSY)
 159                                         return ret;
 160                         }
 161                 }
 162         }
 163         spin_unlock(&bdev->lru_lock);
 164         return 0;
 165 }
 166 EXPORT_SYMBOL(ttm_device_swapout);
 167
 168 static void ttm_init_sysman(struct ttm_device *bdev)
 169 {
 170         struct ttm_resource_manager *man = &bdev->sysman;
 171
 172         /*
 173          * Initialize the system memory buffer type.
 174          * Other types need to be driver / IOCTL initialized.
 175          */
 176         man->use_tt = true;
 177
 178         ttm_resource_manager_init(man, 0);
 179         ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, man);
 180         ttm_resource_manager_set_used(man, true);
 181 }
 182
 183 static void ttm_device_delayed_workqueue(struct work_struct *work)
 184 {
 185         struct ttm_device *bdev =
 186                 container_of(work, struct ttm_device, wq.work);
 187
 188         if (!ttm_bo_delayed_delete(bdev, false))
 189                 schedule_delayed_work(&bdev->wq,
 190                                       ((HZ / 100) < 1) ? 1 : HZ / 100);
 191 }
 192
 193 /**
 194  * ttm_device_init
 195  *
 196  * @bdev: A pointer to a struct ttm_device to initialize.
 197  * @funcs: Function table for the device.
 198  * @dev: The core kernel device pointer for DMA mappings and allocations.
 199  * @mapping: The address space to use for this bo.
 200  * @vma_manager: A pointer to a vma manager.
 201  * @use_dma_alloc: If coherent DMA allocation API should be used.
 202  * @use_dma32: If we should use GFP_DMA32 for device memory allocations.
 203  *
 204  * Initializes a struct ttm_device:
 205  * Returns:
 206  * !0: Failure.
 207  */
 208 int ttm_device_init(struct ttm_device *bdev, struct ttm_device_funcs *funcs,
 209                     struct device *dev, struct address_space *mapping,
 210                     struct drm_vma_offset_manager *vma_manager,
 211                     bool use_dma_alloc, bool use_dma32)
 212 {
 213         struct ttm_global *glob = &ttm_glob;
 214         int ret;
 215
 216         if (WARN_ON(vma_manager == NULL))
 217                 return -EINVAL;
 218
 219         ret = ttm_global_init();
 220         if (ret)
 221                 return ret;
 222
 223         bdev->funcs = funcs;
 224
 225         ttm_init_sysman(bdev);
 226         ttm_pool_init(&bdev->pool, dev, use_dma_alloc, use_dma32);
 227
 228         bdev->vma_manager = vma_manager;
 229         INIT_DELAYED_WORK(&bdev->wq, ttm_device_delayed_workqueue);
 230         spin_lock_init(&bdev->lru_lock);
 231         INIT_LIST_HEAD(&bdev->ddestroy);
 232         bdev->dev_mapping = mapping;
 233         mutex_lock(&ttm_global_mutex);
 234         list_add_tail(&bdev->device_list, &glob->device_list);
 235         mutex_unlock(&ttm_global_mutex);
 236
 237         return 0;
 238 }
 239 EXPORT_SYMBOL(ttm_device_init);
 240
 241 void ttm_device_fini(struct ttm_device *bdev)
 242 {
 243         struct ttm_resource_manager *man;
 244         unsigned i;
 245
 246         man = ttm_manager_type(bdev, TTM_PL_SYSTEM);
 247         ttm_resource_manager_set_used(man, false);
 248         ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, NULL);
 249
 250         mutex_lock(&ttm_global_mutex);
 251         list_del(&bdev->device_list);
 252         mutex_unlock(&ttm_global_mutex);
 253
 254         cancel_delayed_work_sync(&bdev->wq);
 255
 256         if (ttm_bo_delayed_delete(bdev, true))
 257                 pr_debug("Delayed destroy list was clean\n");
 258
 259         spin_lock(&bdev->lru_lock);
 260         for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
 261                 if (list_empty(&man->lru[0]))
 262                         pr_debug("Swap list %d was clean\n", i);
 263         spin_unlock(&bdev->lru_lock);
 264
 265         ttm_pool_fini(&bdev->pool);
 266         ttm_global_release();
 267 }
 268 EXPORT_SYMBOL(ttm_device_fini);