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
 22static void
 23msm_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
 35void 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
 41void
 42msm_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
 62int
 63msm_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
 94struct msm_gem_address_space *
 95msm_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}