drivers/gpu/drm/v3d/v3d_bo.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /* Copyright (C) 2015-2018 Broadcom */
   3
   4 /**
   5  * DOC: V3D GEM BO management support
   6  *
   7  * Compared to VC4 (V3D 2.x), V3D 3.3 introduces an MMU between the
   8  * GPU and the bus, allowing us to use shmem objects for our storage
   9  * instead of CMA.
  10  *
  11  * Physically contiguous objects may still be imported to V3D, but the
  12  * driver doesn't allocate physically contiguous objects on its own.
  13  * Display engines requiring physically contiguous allocations should
  14  * look into Mesa's "renderonly" support (as used by the Mesa pl111
  15  * driver) for an example of how to integrate with V3D.
  16  *
  17  * Long term, we should support evicting pages from the MMU when under
  18  * memory pressure (thus the v3d_bo_get_pages() refcounting), but
  19  * that's not a high priority since our systems tend to not have swap.
  20  */
  21
  22 #include <linux/dma-buf.h>
  23 #include <linux/pfn_t.h>
  24
  25 #include "v3d_drv.h"
  26 #include "uapi/drm/v3d_drm.h"
  27
  28 /* Called DRM core on the last userspace/kernel unreference of the
  29  * BO.
  30  */
  31 void v3d_free_object(struct drm_gem_object *obj)
  32 {
  33         struct v3d_dev *v3d = to_v3d_dev(obj->dev);
  34         struct v3d_bo *bo = to_v3d_bo(obj);
  35
  36         v3d_mmu_remove_ptes(bo);
  37
  38         mutex_lock(&v3d->bo_lock);
  39         v3d->bo_stats.num_allocated--;
  40         v3d->bo_stats.pages_allocated -= obj->size >> PAGE_SHIFT;
  41         mutex_unlock(&v3d->bo_lock);
  42
  43         spin_lock(&v3d->mm_lock);
  44         drm_mm_remove_node(&bo->node);
  45         spin_unlock(&v3d->mm_lock);
  46
  47         /* GPU execution may have dirtied any pages in the BO. */
  48         bo->base.pages_mark_dirty_on_put = true;
  49
  50         drm_gem_shmem_free_object(obj);
  51 }
  52
  53 static const struct drm_gem_object_funcs v3d_gem_funcs = {
  54         .free = v3d_free_object,
  55         .print_info = drm_gem_shmem_print_info,
  56         .pin = drm_gem_shmem_pin,
  57         .unpin = drm_gem_shmem_unpin,
  58         .get_sg_table = drm_gem_shmem_get_sg_table,
  59         .vmap = drm_gem_shmem_vmap,
  60         .vunmap = drm_gem_shmem_vunmap,
  61         .mmap = drm_gem_shmem_mmap,
  62 };
  63
  64 /* gem_create_object function for allocating a BO struct and doing
  65  * early setup.
  66  */
  67 struct drm_gem_object *v3d_create_object(struct drm_device *dev, size_t size)
  68 {
  69         struct v3d_bo *bo;
  70         struct drm_gem_object *obj;
  71
  72         if (size == 0)
  73                 return NULL;
  74
  75         bo = kzalloc(sizeof(*bo), GFP_KERNEL);
  76         if (!bo)
  77                 return NULL;
  78         obj = &bo->base.base;
  79
  80         obj->funcs = &v3d_gem_funcs;
  81         bo->base.map_wc = true;
  82         INIT_LIST_HEAD(&bo->unref_head);
  83
  84         return &bo->base.base;
  85 }
  86
  87 static int
  88 v3d_bo_create_finish(struct drm_gem_object *obj)
  89 {
  90         struct v3d_dev *v3d = to_v3d_dev(obj->dev);
  91         struct v3d_bo *bo = to_v3d_bo(obj);
  92         struct sg_table *sgt;
  93         int ret;
  94
  95         /* So far we pin the BO in the MMU for its lifetime, so use
  96          * shmem's helper for getting a lifetime sgt.
  97          */
  98         sgt = drm_gem_shmem_get_pages_sgt(&bo->base.base);
  99         if (IS_ERR(sgt))
 100                 return PTR_ERR(sgt);
 101
 102         spin_lock(&v3d->mm_lock);
 103         /* Allocate the object's space in the GPU's page tables.
 104          * Inserting PTEs will happen later, but the offset is for the
 105          * lifetime of the BO.
 106          */
 107         ret = drm_mm_insert_node_generic(&v3d->mm, &bo->node,
 108                                          obj->size >> PAGE_SHIFT,
 109                                          GMP_GRANULARITY >> PAGE_SHIFT, 0, 0);
 110         spin_unlock(&v3d->mm_lock);
 111         if (ret)
 112                 return ret;
 113
 114         /* Track stats for /debug/dri/n/bo_stats. */
 115         mutex_lock(&v3d->bo_lock);
 116         v3d->bo_stats.num_allocated++;
 117         v3d->bo_stats.pages_allocated += obj->size >> PAGE_SHIFT;
 118         mutex_unlock(&v3d->bo_lock);
 119
 120         v3d_mmu_insert_ptes(bo);
 121
 122         return 0;
 123 }
 124
 125 struct v3d_bo *v3d_bo_create(struct drm_device *dev, struct drm_file *file_priv,
 126                              size_t unaligned_size)
 127 {
 128         struct drm_gem_shmem_object *shmem_obj;
 129         struct v3d_bo *bo;
 130         int ret;
 131
 132         shmem_obj = drm_gem_shmem_create(dev, unaligned_size);
 133         if (IS_ERR(shmem_obj))
 134                 return ERR_CAST(shmem_obj);
 135         bo = to_v3d_bo(&shmem_obj->base);
 136
 137         ret = v3d_bo_create_finish(&shmem_obj->base);
 138         if (ret)
 139                 goto free_obj;
 140
 141         return bo;
 142
 143 free_obj:
 144         drm_gem_shmem_free_object(&shmem_obj->base);
 145         return ERR_PTR(ret);
 146 }
 147
 148 struct drm_gem_object *
 149 v3d_prime_import_sg_table(struct drm_device *dev,
 150                           struct dma_buf_attachment *attach,
 151                           struct sg_table *sgt)
 152 {
 153         struct drm_gem_object *obj;
 154         int ret;
 155
 156         obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt);
 157         if (IS_ERR(obj))
 158                 return obj;
 159
 160         ret = v3d_bo_create_finish(obj);
 161         if (ret) {
 162                 drm_gem_shmem_free_object(obj);
 163                 return ERR_PTR(ret);
 164         }
 165
 166         return obj;
 167 }
 168
 169 int v3d_create_bo_ioctl(struct drm_device *dev, void *data,
 170                         struct drm_file *file_priv)
 171 {
 172         struct drm_v3d_create_bo *args = data;
 173         struct v3d_bo *bo = NULL;
 174         int ret;
 175
 176         if (args->flags != 0) {
 177                 DRM_INFO("unknown create_bo flags: %d\n", args->flags);
 178                 return -EINVAL;
 179         }
 180
 181         bo = v3d_bo_create(dev, file_priv, PAGE_ALIGN(args->size));
 182         if (IS_ERR(bo))
 183                 return PTR_ERR(bo);
 184
 185         args->offset = bo->node.start << PAGE_SHIFT;
 186
 187         ret = drm_gem_handle_create(file_priv, &bo->base.base, &args->handle);
 188         drm_gem_object_put(&bo->base.base);
 189
 190         return ret;
 191 }
 192
 193 int v3d_mmap_bo_ioctl(struct drm_device *dev, void *data,
 194                       struct drm_file *file_priv)
 195 {
 196         struct drm_v3d_mmap_bo *args = data;
 197         struct drm_gem_object *gem_obj;
 198
 199         if (args->flags != 0) {
 200                 DRM_INFO("unknown mmap_bo flags: %d\n", args->flags);
 201                 return -EINVAL;
 202         }
 203
 204         gem_obj = drm_gem_object_lookup(file_priv, args->handle);
 205         if (!gem_obj) {
 206                 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
 207                 return -ENOENT;
 208         }
 209
 210         args->offset = drm_vma_node_offset_addr(&gem_obj->vma_node);
 211         drm_gem_object_put(gem_obj);
 212
 213         return 0;
 214 }
 215
 216 int v3d_get_bo_offset_ioctl(struct drm_device *dev, void *data,
 217                             struct drm_file *file_priv)
 218 {
 219         struct drm_v3d_get_bo_offset *args = data;
 220         struct drm_gem_object *gem_obj;
 221         struct v3d_bo *bo;
 222
 223         gem_obj = drm_gem_object_lookup(file_priv, args->handle);
 224         if (!gem_obj) {
 225                 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
 226                 return -ENOENT;
 227         }
 228         bo = to_v3d_bo(gem_obj);
 229
 230         args->offset = bo->node.start << PAGE_SHIFT;
 231
 232         drm_gem_object_put(gem_obj);
 233         return 0;
 234 }