--- /dev/null
+/* exynos_drm_dmabuf.c
+ *
+ * Copyright (c) 2012 Samsung Electronics Co., Ltd.
+ * Author: Inki Dae <inki.dae@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <drm/drmP.h>
+#include <drm/exynos_drm.h>
+#include "exynos_drm_dmabuf.h"
+#include "exynos_drm_drv.h"
+#include "exynos_drm_gem.h"
+
+#include <linux/dma-buf.h>
+
+struct exynos_drm_dmabuf_attachment {
+ struct sg_table sgt;
+ enum dma_data_direction dir;
+ bool is_mapped;
+};
+
+static struct exynos_drm_gem_obj *dma_buf_to_obj(struct dma_buf *buf)
+{
+ return to_exynos_gem_obj(buf->priv);
+}
+
+static int exynos_gem_attach_dma_buf(struct dma_buf *dmabuf,
+ struct device *dev,
+ struct dma_buf_attachment *attach)
+{
+ struct exynos_drm_dmabuf_attachment *exynos_attach;
+
+ exynos_attach = kzalloc(sizeof(*exynos_attach), GFP_KERNEL);
+ if (!exynos_attach)
+ return -ENOMEM;
+
+ exynos_attach->dir = DMA_NONE;
+ attach->priv = exynos_attach;
+
+ return 0;
+}
+
+static void exynos_gem_detach_dma_buf(struct dma_buf *dmabuf,
+ struct dma_buf_attachment *attach)
+{
+ struct exynos_drm_dmabuf_attachment *exynos_attach = attach->priv;
+ struct sg_table *sgt;
+
+ if (!exynos_attach)
+ return;
+
+ sgt = &exynos_attach->sgt;
+
+ if (exynos_attach->dir != DMA_NONE)
+ dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents,
+ exynos_attach->dir);
+
+ sg_free_table(sgt);
+ kfree(exynos_attach);
+ attach->priv = NULL;
+}
+
+static struct sg_table *
+ exynos_gem_map_dma_buf(struct dma_buf_attachment *attach,
+ enum dma_data_direction dir)
+{
+ struct exynos_drm_dmabuf_attachment *exynos_attach = attach->priv;
+ struct exynos_drm_gem_obj *gem_obj = dma_buf_to_obj(attach->dmabuf);
+ struct drm_device *dev = gem_obj->base.dev;
+ struct exynos_drm_gem_buf *buf;
+ struct scatterlist *rd, *wr;
+ struct sg_table *sgt = NULL;
+ unsigned int i;
+ int nents, ret;
+
+ /* just return current sgt if already requested. */
+ if (exynos_attach->dir == dir && exynos_attach->is_mapped)
+ return &exynos_attach->sgt;
+
+ buf = gem_obj->buffer;
+ if (!buf) {
+ DRM_ERROR("buffer is null.\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ sgt = &exynos_attach->sgt;
+
+ ret = sg_alloc_table(sgt, buf->sgt->orig_nents, GFP_KERNEL);
+ if (ret) {
+ DRM_ERROR("failed to alloc sgt.\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ mutex_lock(&dev->struct_mutex);
+
+ rd = buf->sgt->sgl;
+ wr = sgt->sgl;
+ for (i = 0; i < sgt->orig_nents; ++i) {
+ sg_set_page(wr, sg_page(rd), rd->length, rd->offset);
+ rd = sg_next(rd);
+ wr = sg_next(wr);
+ }
+
+ if (dir != DMA_NONE) {
+ nents = dma_map_sg(attach->dev, sgt->sgl, sgt->orig_nents, dir);
+ if (!nents) {
+ DRM_ERROR("failed to map sgl with iommu.\n");
+ sg_free_table(sgt);
+ sgt = ERR_PTR(-EIO);
+ goto err_unlock;
+ }
+ }
+
+ exynos_attach->is_mapped = true;
+ exynos_attach->dir = dir;
+ attach->priv = exynos_attach;
+
+ DRM_DEBUG_PRIME("buffer size = 0x%lx\n", buf->size);
+
+err_unlock:
+ mutex_unlock(&dev->struct_mutex);
+ return sgt;
+}
+
+static void exynos_gem_unmap_dma_buf(struct dma_buf_attachment *attach,
+ struct sg_table *sgt,
+ enum dma_data_direction dir)
+{
+ /* Nothing to do. */
+}
+
+static void *exynos_gem_dmabuf_kmap_atomic(struct dma_buf *dma_buf,
+ unsigned long page_num)
+{
+ /* TODO */
+
+ return NULL;
+}
+
+static void exynos_gem_dmabuf_kunmap_atomic(struct dma_buf *dma_buf,
+ unsigned long page_num,
+ void *addr)
+{
+ /* TODO */
+}
+
+static void *exynos_gem_dmabuf_kmap(struct dma_buf *dma_buf,
+ unsigned long page_num)
+{
+ /* TODO */
+
+ return NULL;
+}
+
+static void exynos_gem_dmabuf_kunmap(struct dma_buf *dma_buf,
+ unsigned long page_num, void *addr)
+{
+ /* TODO */
+}
+
+static int exynos_gem_dmabuf_mmap(struct dma_buf *dma_buf,
+ struct vm_area_struct *vma)
+{
+ return -ENOTTY;
+}
+
+static struct dma_buf_ops exynos_dmabuf_ops = {
+ .attach = exynos_gem_attach_dma_buf,
+ .detach = exynos_gem_detach_dma_buf,
+ .map_dma_buf = exynos_gem_map_dma_buf,
+ .unmap_dma_buf = exynos_gem_unmap_dma_buf,
+ .kmap = exynos_gem_dmabuf_kmap,
+ .kmap_atomic = exynos_gem_dmabuf_kmap_atomic,
+ .kunmap = exynos_gem_dmabuf_kunmap,
+ .kunmap_atomic = exynos_gem_dmabuf_kunmap_atomic,
+ .mmap = exynos_gem_dmabuf_mmap,
+ .release = drm_gem_dmabuf_release,
+};
+
+struct dma_buf *exynos_dmabuf_prime_export(struct drm_device *drm_dev,
+ struct drm_gem_object *obj, int flags)
+{
+ struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
+ DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
+
+ exp_info.ops = &exynos_dmabuf_ops;
+ exp_info.size = exynos_gem_obj->base.size;
+ exp_info.flags = flags;
+ exp_info.priv = obj;
+
+ return dma_buf_export(&exp_info);
+}
+
+struct drm_gem_object *exynos_dmabuf_prime_import(struct drm_device *drm_dev,
+ struct dma_buf *dma_buf)
+{
+ struct dma_buf_attachment *attach;
+ struct sg_table *sgt;
+ struct scatterlist *sgl;
+ struct exynos_drm_gem_obj *exynos_gem_obj;
+ struct exynos_drm_gem_buf *buffer;
+ int ret;
+
+ /* is this one of own objects? */
+ if (dma_buf->ops == &exynos_dmabuf_ops) {
+ struct drm_gem_object *obj;
+
+ obj = dma_buf->priv;
+
+ /* is it from our device? */
+ if (obj->dev == drm_dev) {
+ /*
+ * Importing dmabuf exported from out own gem increases
+ * refcount on gem itself instead of f_count of dmabuf.
+ */
+ drm_gem_object_reference(obj);
+ return obj;
+ }
+ }
+
+ attach = dma_buf_attach(dma_buf, drm_dev->dev);
+ if (IS_ERR(attach))
+ return ERR_PTR(-EINVAL);
+
+ get_dma_buf(dma_buf);
+
+ sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
+ if (IS_ERR(sgt)) {
+ ret = PTR_ERR(sgt);
+ goto err_buf_detach;
+ }
+
+ buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
+ if (!buffer) {
+ ret = -ENOMEM;
+ goto err_unmap_attach;
+ }
+
+ exynos_gem_obj = exynos_drm_gem_init(drm_dev, dma_buf->size);
+ if (!exynos_gem_obj) {
+ ret = -ENOMEM;
+ goto err_free_buffer;
+ }
+
+ sgl = sgt->sgl;
+
+ buffer->size = dma_buf->size;
+ buffer->dma_addr = sg_dma_address(sgl);
+
+ if (sgt->nents == 1) {
+ /* always physically continuous memory if sgt->nents is 1. */
+ exynos_gem_obj->flags |= EXYNOS_BO_CONTIG;
+ } else {
+ /*
+ * this case could be CONTIG or NONCONTIG type but for now
+ * sets NONCONTIG.
+ * TODO. we have to find a way that exporter can notify
+ * the type of its own buffer to importer.
+ */
+ exynos_gem_obj->flags |= EXYNOS_BO_NONCONTIG;
+ }
+
+ exynos_gem_obj->buffer = buffer;
+ buffer->sgt = sgt;
+ exynos_gem_obj->base.import_attach = attach;
+
+ DRM_DEBUG_PRIME("dma_addr = %pad, size = 0x%lx\n", &buffer->dma_addr,
+ buffer->size);
+
+ return &exynos_gem_obj->base;
+
+err_free_buffer:
+ kfree(buffer);
+ buffer = NULL;
+err_unmap_attach:
+ dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL);
+err_buf_detach:
+ dma_buf_detach(dma_buf, attach);
+ dma_buf_put(dma_buf);
+
+ return ERR_PTR(ret);
+}
Code Review / kvmfornfv.git / blobdiff