+diff --git a/drivers/gpu/Makefile b/drivers/gpu/Makefile
+index 30879df..35699a0 100644
+--- a/drivers/gpu/Makefile
++++ b/drivers/gpu/Makefile
+@@ -1 +1 @@
+-obj-y += drm/ vga/ stub/
++obj-y += drm/ vga/ stub/ misc/
+diff --git a/drivers/gpu/misc/Kconfig b/drivers/gpu/misc/Kconfig
+new file mode 100644
+index 0000000..50043d3
+--- /dev/null
++++ b/drivers/gpu/misc/Kconfig
+@@ -0,0 +1,8 @@
++config VIRTIOGL
++ tristate "Virtio userspace memory transport"
++ depends on VIRTIO_PCI
++ default n
++ help
++ A Driver to facilitate transferring data from userspace to a
++ hypervisor (eg. qemu)
++
+diff --git a/drivers/gpu/misc/Makefile b/drivers/gpu/misc/Makefile
+new file mode 100644
+index 0000000..d9ab333
+--- /dev/null
++++ b/drivers/gpu/misc/Makefile
+@@ -0,0 +1 @@
++obj-$(CONFIG_VIRTIOGL) += virtio-gl.o
+diff --git a/drivers/gpu/misc/virtio-gl.c b/drivers/gpu/misc/virtio-gl.c
+new file mode 100644
+index 0000000..8882bda
+--- /dev/null
++++ b/drivers/gpu/misc/virtio-gl.c
+@@ -0,0 +1,312 @@
++/*
++ * Copyright (C) 2010 Intel Corporation
++ *
++ * Author: Ian Molton <ian.molton@collabora.co.uk>
++ *
++ * 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.
++ *
++ * This program is distributed in the hope that it will be useful,
++ * but WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
++ * GNU General Public License for more details.
++ *
++ * You should have received a copy of the GNU General Public License
++ * along with this program; if not, write to the Free Software
++ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
++ */
++
++#include <linux/kernel.h>
++#include <linux/module.h>
++#include <linux/fs.h>
++#include <linux/dma-mapping.h>
++#include <linux/sched.h>
++#include <linux/slab.h>
++#include <linux/miscdevice.h>
++#include <linux/virtio.h>
++#include <linux/virtio_ids.h>
++#include <linux/virtio_config.h>
++
++#define DEVICE_NAME "glmem"
++
++/* Define to use debugging checksums on transfers */
++#undef DEBUG_GLIO
++
++struct virtio_gl_data {
++ char *buffer;
++ int pages;
++ unsigned int pid;
++};
++
++struct virtio_gl_header {
++ int pid;
++ int buf_size;
++ int r_buf_size;
++#ifdef DEBUG_GLIO
++ int sum;
++#endif
++ char buffer;
++} __packed;
++
++#define to_virtio_gl_data(a) ((struct virtio_gl_data *)(a)->private_data)
++
++#ifdef DEBUG_GLIO
++#define SIZE_OUT_HEADER (sizeof(int)*4)
++#define SIZE_IN_HEADER (sizeof(int)*2)
++#else
++#define SIZE_OUT_HEADER (sizeof(int)*3)
++#define SIZE_IN_HEADER sizeof(int)
++#endif
++
++static struct virtqueue *vq;
++
++
++/* This is videobuf_vmalloc_to_sg() from videobuf-dma-sg.c with
++ * some modifications
++ */
++static struct scatterlist *vmalloc_to_sg(struct scatterlist *sg_list,
++ unsigned char *virt, unsigned int pages)
++{
++ struct page *pg;
++
++ /* unaligned */
++ BUG_ON((ulong)virt & ~PAGE_MASK);
++
++ /* Fill with elements for the data */
++ while (pages) {
++ pg = vmalloc_to_page(virt);
++ if (!pg)
++ goto err;
++
++ sg_set_page(sg_list, pg, PAGE_SIZE, 0);
++ virt += PAGE_SIZE;
++ sg_list++;
++ pages--;
++ }
++
++ return sg_list;
++
++err:
++ kfree(sg_list);
++ return NULL;
++}
++
++static int put_data(struct virtio_gl_data *gldata)
++{
++ struct scatterlist *sg, *sg_list;
++ unsigned int count, ret, o_page, i_page, sg_entries;
++ struct virtio_gl_header *header =
++ (struct virtio_gl_header *)gldata->buffer;
++
++ ret = header->buf_size;
++
++ o_page = (header->buf_size + PAGE_SIZE-1) >> PAGE_SHIFT;
++ i_page = (header->r_buf_size + PAGE_SIZE-1) >> PAGE_SHIFT;
++
++ header->pid = gldata->pid;
++
++ if ((o_page && i_page) &&
++ (o_page > gldata->pages || i_page > gldata->pages)) {
++ i_page = 0;
++ }
++
++ if (o_page > gldata->pages)
++ o_page = gldata->pages;
++
++ if (i_page > gldata->pages)
++ i_page = gldata->pages;
++
++ if (!o_page)
++ o_page = 1;
++
++ sg_entries = o_page + i_page;
++
++ sg_list = kcalloc(sg_entries, sizeof(struct scatterlist), GFP_KERNEL);
++
++ if (!sg_list) {
++ ret = -EIO;
++ goto out;
++ }
++
++ sg_init_table(sg_list, sg_entries);
++
++ sg = vmalloc_to_sg(sg_list, gldata->buffer, o_page);
++ sg = vmalloc_to_sg(sg, gldata->buffer, i_page);
++
++ if (!sg) {
++ ret = -EIO;
++ goto out_free;
++ }
++
++ /* Transfer data */
++ if (virtqueue_add_buf(vq, sg_list, o_page, i_page, (void *)1) >= 0) {
++ virtqueue_kick(vq);
++ /* Chill out until it's done with the buffer. */
++ while (!virtqueue_get_buf(vq, &count))
++ cpu_relax();
++ }
++
++out_free:
++ kfree(sg_list);
++out:
++ return ret;
++}
++
++static void free_buffer(struct virtio_gl_data *gldata)
++{
++ if (gldata->buffer) {
++ vfree(gldata->buffer);
++ gldata->buffer = NULL;
++ }
++}
++
++static int glmem_open(struct inode *inode, struct file *file)
++{
++ struct virtio_gl_data *gldata = kzalloc(sizeof(struct virtio_gl_data),
++ GFP_KERNEL);
++
++ if (!gldata)
++ return -ENXIO;
++
++ gldata->pid = pid_nr(task_pid(current));
++
++ file->private_data = gldata;
++
++ return 0;
++}
++
++static int glmem_mmap(struct file *filp, struct vm_area_struct *vma)
++{
++ struct virtio_gl_data *gldata = to_virtio_gl_data(filp);
++ int pages = (vma->vm_end - vma->vm_start) / PAGE_SIZE;
++
++ /* Set a reasonable limit */
++ if (pages > 16)
++ return -ENOMEM;
++
++ /* for now, just allow one buffer to be mmap()ed. */
++ if (gldata->buffer)
++ return -EIO;
++
++ gldata->buffer = vmalloc_user(pages*PAGE_SIZE);
++
++ if (!gldata->buffer)
++ return -ENOMEM;
++
++ gldata->pages = pages;
++
++ if (remap_vmalloc_range(vma, gldata->buffer, 0) < 0) {
++ vfree(gldata->buffer);
++ return -EIO;
++ }
++
++ vma->vm_flags |= VM_DONTEXPAND;
++
++ return 0;
++}
++
++static int glmem_fsync(struct file *filp, int datasync)
++{
++ struct virtio_gl_data *gldata = to_virtio_gl_data(filp);
++
++ put_data(gldata);
++
++ return 0;
++}
++
++static int glmem_release(struct inode *inode, struct file *file)
++{
++ struct virtio_gl_data *gldata = to_virtio_gl_data(file);
++
++ if (gldata && gldata->buffer) {
++ struct virtio_gl_header *header =
++ (struct virtio_gl_header *)gldata->buffer;
++
++ /* Make sure the host hears about the process ending / dying */
++ header->pid = gldata->pid;
++ header->buf_size = SIZE_OUT_HEADER + 2;
++ header->r_buf_size = SIZE_IN_HEADER;
++ *(short *)(&header->buffer) = -1;
++
++ put_data(gldata);
++ free_buffer(gldata);
++ }
++
++ kfree(gldata);
++
++ return 0;
++}
++
++static const struct file_operations glmem_fops = {
++ .owner = THIS_MODULE,
++ .open = glmem_open,
++ .mmap = glmem_mmap,
++ .fsync = glmem_fsync,
++ .release = glmem_release,
++};
++
++static struct miscdevice glmem_dev = {
++ MISC_DYNAMIC_MINOR,
++ DEVICE_NAME,
++ &glmem_fops
++};
++
++static int glmem_probe(struct virtio_device *vdev)
++{
++ int ret;
++
++ /* We expect a single virtqueue. */
++ vq = virtio_find_single_vq(vdev, NULL, "output");
++ if (IS_ERR(vq))
++ return PTR_ERR(vq);
++
++ ret = misc_register(&glmem_dev);
++ if (ret) {
++ printk(KERN_ERR "glmem: cannot register glmem_dev as misc");
++ return -ENODEV;
++ }
++
++ return 0;
++}
++
++static void __devexit glmem_remove(struct virtio_device *vdev)
++{
++ vdev->config->reset(vdev);
++ misc_deregister(&glmem_dev);
++ vdev->config->del_vqs(vdev);
++}
++
++static struct virtio_device_id id_table[] = {
++ { VIRTIO_ID_GL, VIRTIO_DEV_ANY_ID },
++ { 0 },
++};
++
++static struct virtio_driver virtio_gl_driver = {
++ .driver = {
++ .name = KBUILD_MODNAME,
++ .owner = THIS_MODULE,
++ },
++ .id_table = id_table,
++ .probe = glmem_probe,
++ .remove = __devexit_p(glmem_remove),
++};
++
++static int __init glmem_init(void)
++{
++ return register_virtio_driver(&virtio_gl_driver);
++}
++
++static void __exit glmem_exit(void)
++{
++ unregister_virtio_driver(&virtio_gl_driver);
++}
++
++module_init(glmem_init);
++module_exit(glmem_exit);
++
++MODULE_DEVICE_TABLE(virtio, id_table);
++MODULE_DESCRIPTION("Virtio gl passthrough driver");
++MODULE_LICENSE("GPL v2");
++
+diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
+index 3d94a14..9a9a6cc 100644
+--- a/drivers/video/Kconfig
++++ b/drivers/video/Kconfig
+@@ -16,6 +16,7 @@ source "drivers/char/agp/Kconfig"
+ source "drivers/gpu/vga/Kconfig"
+
+ source "drivers/gpu/drm/Kconfig"
++source "drivers/gpu/misc/Kconfig"
+
+ config VGASTATE
+ tristate
+diff --git a/include/linux/virtio_ids.h b/include/linux/virtio_ids.h
+index 06660c0..663b496 100644
+--- a/include/linux/virtio_ids.h
++++ b/include/linux/virtio_ids.h
+@@ -12,6 +12,7 @@
+ #define VIRTIO_ID_CONSOLE 3 /* virtio console */
+ #define VIRTIO_ID_RNG 4 /* virtio ring */
+ #define VIRTIO_ID_BALLOON 5 /* virtio balloon */
++#define VIRTIO_ID_GL 6 /* virtio usermem */
+ #define VIRTIO_ID_9P 9 /* 9p virtio console */
+
+ #endif /* _LINUX_VIRTIO_IDS_H */
+
+
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