+++ /dev/null
-/*
- * 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; version 2 of the License.
- *
- * 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/mutex.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;
-
-static DEFINE_MUTEX(gl_mutex);
-
-/* 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;
-
- mutex_lock(&gl_mutex);
-
- 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;
- }
-
-#if 0
- /* The fifth parameter of virtqueue_add_buf : FIX ME */
- /* Transfer data */
- if (virtqueue_add_buf(vq, sg_list, o_page, i_page, (void *)1, GFP_ATOMIC) >= 0) {
- virtqueue_kick(vq);
- /* Chill out until it's done with the buffer. */
- while (!virtqueue_get_buf(vq, &count))
- cpu_relax();
- }
-#endif
- /* The fourth parameter of virtqueue_add_buf : FIX ME */
- /* Transfer data */
- if ((virtqueue_add_outbuf(vq, sg_list, o_page, (void *)1, GFP_ATOMIC) >= 0) &&
- (virtqueue_add_inbuf(vq, sg_list, i_page, (void *)1, GFP_ATOMIC) >= 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:
- mutex_unlock(&gl_mutex);
- 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, loff_t start, loff_t end, 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 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 = 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");
-
projects / sdk / emulator / emulator-kernel.git / commitdiff