drivers/gpu/drm/msm/msm_gem_vma.c

   1 /*
   2  * Copyright (C) 2016 Red Hat
   3  * Author: Rob Clark <robdclark@gmail.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 as published by
   7  * the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "msm_drv.h"
  19 #include "msm_gem.h"
  20 #include "msm_mmu.h"
  21
  22 static void
  23 msm_gem_address_space_destroy(struct kref *kref)
  24 {
  25         struct msm_gem_address_space *aspace = container_of(kref,
  26                         struct msm_gem_address_space, kref);
  27
  28         drm_mm_takedown(&aspace->mm);
  29         if (aspace->mmu)
  30                 aspace->mmu->funcs->destroy(aspace->mmu);
  31         kfree(aspace);
  32 }
  33
  34
  35 void msm_gem_address_space_put(struct msm_gem_address_space *aspace)
  36 {
  37         if (aspace)
  38                 kref_put(&aspace->kref, msm_gem_address_space_destroy);
  39 }
  40
  41 void
  42 msm_gem_unmap_vma(struct msm_gem_address_space *aspace,
  43                 struct msm_gem_vma *vma, struct sg_table *sgt)
  44 {
  45         if (!aspace || !vma->iova)
  46                 return;
  47
  48         if (aspace->mmu) {
  49                 unsigned size = vma->node.size << PAGE_SHIFT;
  50                 aspace->mmu->funcs->unmap(aspace->mmu, vma->iova, sgt, size);
  51         }
  52
  53         spin_lock(&aspace->lock);
  54         drm_mm_remove_node(&vma->node);
  55         spin_unlock(&aspace->lock);
  56
  57         vma->iova = 0;
  58
  59         msm_gem_address_space_put(aspace);
  60 }
  61
  62 int
  63 msm_gem_map_vma(struct msm_gem_address_space *aspace,
  64                 struct msm_gem_vma *vma, struct sg_table *sgt, int npages)
  65 {
  66         int ret;
  67
  68         spin_lock(&aspace->lock);
  69         if (WARN_ON(drm_mm_node_allocated(&vma->node))) {
  70                 spin_unlock(&aspace->lock);
  71                 return 0;
  72         }
  73
  74         ret = drm_mm_insert_node(&aspace->mm, &vma->node, npages);
  75         spin_unlock(&aspace->lock);
  76
  77         if (ret)
  78                 return ret;
  79
  80         vma->iova = vma->node.start << PAGE_SHIFT;
  81
  82         if (aspace->mmu) {
  83                 unsigned size = npages << PAGE_SHIFT;
  84                 ret = aspace->mmu->funcs->map(aspace->mmu, vma->iova, sgt,
  85                                 size, IOMMU_READ | IOMMU_WRITE);
  86         }
  87
  88         /* Get a reference to the aspace to keep it around */
  89         kref_get(&aspace->kref);
  90
  91         return ret;
  92 }
  93
  94 struct msm_gem_address_space *
  95 msm_gem_address_space_create(struct device *dev, struct iommu_domain *domain,
  96                 const char *name)
  97 {
  98         struct msm_gem_address_space *aspace;
  99         u64 size = domain->geometry.aperture_end -
 100                 domain->geometry.aperture_start;
 101
 102         aspace = kzalloc(sizeof(*aspace), GFP_KERNEL);
 103         if (!aspace)
 104                 return ERR_PTR(-ENOMEM);
 105
 106         spin_lock_init(&aspace->lock);
 107         aspace->name = name;
 108         aspace->mmu = msm_iommu_new(dev, domain);
 109
 110         drm_mm_init(&aspace->mm, (domain->geometry.aperture_start >> PAGE_SHIFT),
 111                 size >> PAGE_SHIFT);
 112
 113         kref_init(&aspace->kref);
 114
 115         return aspace;
 116 }