drivers/gpu/drm/msm/msm_gem_vma.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2016 Red Hat
   4  * Author: Rob Clark <robdclark@gmail.com>
   5  */
   6
   7 #include "msm_drv.h"
   8 #include "msm_gem.h"
   9 #include "msm_mmu.h"
  10
  11 static void
  12 msm_gem_address_space_destroy(struct kref *kref)
  13 {
  14         struct msm_gem_address_space *aspace = container_of(kref,
  15                         struct msm_gem_address_space, kref);
  16
  17         drm_mm_takedown(&aspace->mm);
  18         if (aspace->mmu)
  19                 aspace->mmu->funcs->destroy(aspace->mmu);
  20         put_pid(aspace->pid);
  21         kfree(aspace);
  22 }
  23
  24
  25 void msm_gem_address_space_put(struct msm_gem_address_space *aspace)
  26 {
  27         if (aspace)
  28                 kref_put(&aspace->kref, msm_gem_address_space_destroy);
  29 }
  30
  31 struct msm_gem_address_space *
  32 msm_gem_address_space_get(struct msm_gem_address_space *aspace)
  33 {
  34         if (!IS_ERR_OR_NULL(aspace))
  35                 kref_get(&aspace->kref);
  36
  37         return aspace;
  38 }
  39
  40 /* Actually unmap memory for the vma */
  41 void msm_gem_purge_vma(struct msm_gem_address_space *aspace,
  42                 struct msm_gem_vma *vma)
  43 {
  44         unsigned size = vma->node.size << PAGE_SHIFT;
  45
  46         /* Print a message if we try to purge a vma in use */
  47         if (WARN_ON(vma->inuse > 0))
  48                 return;
  49
  50         /* Don't do anything if the memory isn't mapped */
  51         if (!vma->mapped)
  52                 return;
  53
  54         if (aspace->mmu)
  55                 aspace->mmu->funcs->unmap(aspace->mmu, vma->iova, size);
  56
  57         vma->mapped = false;
  58 }
  59
  60 /* Remove reference counts for the mapping */
  61 void msm_gem_unmap_vma(struct msm_gem_address_space *aspace,
  62                 struct msm_gem_vma *vma)
  63 {
  64         if (!WARN_ON(!vma->iova))
  65                 vma->inuse--;
  66 }
  67
  68 int
  69 msm_gem_map_vma(struct msm_gem_address_space *aspace,
  70                 struct msm_gem_vma *vma, int prot,
  71                 struct sg_table *sgt, int npages)
  72 {
  73         unsigned size = npages << PAGE_SHIFT;
  74         int ret = 0;
  75
  76         if (WARN_ON(!vma->iova))
  77                 return -EINVAL;
  78
  79         /* Increase the usage counter */
  80         vma->inuse++;
  81
  82         if (vma->mapped)
  83                 return 0;
  84
  85         vma->mapped = true;
  86
  87         if (aspace && aspace->mmu)
  88                 ret = aspace->mmu->funcs->map(aspace->mmu, vma->iova, sgt,
  89                                 size, prot);
  90
  91         if (ret) {
  92                 vma->mapped = false;
  93                 vma->inuse--;
  94         }
  95
  96         return ret;
  97 }
  98
  99 /* Close an iova.  Warn if it is still in use */
 100 void msm_gem_close_vma(struct msm_gem_address_space *aspace,
 101                 struct msm_gem_vma *vma)
 102 {
 103         if (WARN_ON(vma->inuse > 0 || vma->mapped))
 104                 return;
 105
 106         spin_lock(&aspace->lock);
 107         if (vma->iova)
 108                 drm_mm_remove_node(&vma->node);
 109         spin_unlock(&aspace->lock);
 110
 111         vma->iova = 0;
 112
 113         msm_gem_address_space_put(aspace);
 114 }
 115
 116 /* Initialize a new vma and allocate an iova for it */
 117 int msm_gem_init_vma(struct msm_gem_address_space *aspace,
 118                 struct msm_gem_vma *vma, int npages,
 119                 u64 range_start, u64 range_end)
 120 {
 121         int ret;
 122
 123         if (WARN_ON(vma->iova))
 124                 return -EBUSY;
 125
 126         spin_lock(&aspace->lock);
 127         ret = drm_mm_insert_node_in_range(&aspace->mm, &vma->node, npages, 0,
 128                 0, range_start, range_end, 0);
 129         spin_unlock(&aspace->lock);
 130
 131         if (ret)
 132                 return ret;
 133
 134         vma->iova = vma->node.start << PAGE_SHIFT;
 135         vma->mapped = false;
 136
 137         kref_get(&aspace->kref);
 138
 139         return 0;
 140 }
 141
 142 struct msm_gem_address_space *
 143 msm_gem_address_space_create(struct msm_mmu *mmu, const char *name,
 144                 u64 va_start, u64 size)
 145 {
 146         struct msm_gem_address_space *aspace;
 147
 148         if (IS_ERR(mmu))
 149                 return ERR_CAST(mmu);
 150
 151         aspace = kzalloc(sizeof(*aspace), GFP_KERNEL);
 152         if (!aspace)
 153                 return ERR_PTR(-ENOMEM);
 154
 155         spin_lock_init(&aspace->lock);
 156         aspace->name = name;
 157         aspace->mmu = mmu;
 158
 159         drm_mm_init(&aspace->mm, va_start >> PAGE_SHIFT, size >> PAGE_SHIFT);
 160
 161         kref_init(&aspace->kref);
 162
 163         return aspace;
 164 }