int
ttm_bo_mmap_single(struct ttm_bo_device *bdev, vm_ooffset_t *offset, vm_size_t size,
struct vm_object **obj_res, int nprot)
{
struct ttm_bo_driver *driver;
struct ttm_buffer_object *bo;
struct vm_object *vm_obj;
int ret;
*obj_res = NULL;
lockmgr(&bdev->vm_lock, LK_EXCLUSIVE);
bo = ttm_bo_vm_lookup_rb(bdev, OFF_TO_IDX(*offset), OFF_TO_IDX(size));
if (likely(bo != NULL))
kref_get(&bo->kref);
lockmgr(&bdev->vm_lock, LK_RELEASE);
if (unlikely(bo == NULL)) {
kprintf("[TTM] Could not find buffer object to map\n");
return (EINVAL);
}
driver = bo->bdev->driver;
if (unlikely(!driver->verify_access)) {
ret = EPERM;
goto out_unref;
}
ret = -driver->verify_access(bo);
if (unlikely(ret != 0))
goto out_unref;
vm_obj = cdev_pager_allocate(bo, OBJT_MGTDEVICE, &ttm_pager_ops,
size, nprot, 0, curthread->td_ucred);
if (vm_obj == NULL) {
ret = EINVAL;
goto out_unref;
}
/*
* Note: We're transferring the bo reference to vm_obj->handle here.
*/
*offset = 0;
*obj_res = vm_obj;
return 0;
out_unref:
ttm_bo_unref(&bo);
return ret;
}
ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
const char __user *wbuf, char __user *rbuf, size_t count,
loff_t *f_pos, bool write)
{
struct ttm_buffer_object *bo;
struct ttm_bo_driver *driver;
struct ttm_bo_kmap_obj map;
unsigned long dev_offset = (*f_pos >> PAGE_SHIFT);
unsigned long kmap_offset;
unsigned long kmap_end;
unsigned long kmap_num;
size_t io_size;
unsigned int page_offset;
char *virtual;
int ret;
bool no_wait = false;
bool dummy;
read_lock(&bdev->vm_lock);
bo = ttm_bo_vm_lookup_rb(bdev, dev_offset, 1);
if (likely(bo != NULL))
ttm_bo_reference(bo);
read_unlock(&bdev->vm_lock);
if (unlikely(bo == NULL))
return -EFAULT;
driver = bo->bdev->driver;
if (unlikely(!driver->verify_access)) {
ret = -EPERM;
goto out_unref;
}
ret = driver->verify_access(bo, filp);
if (unlikely(ret != 0))
goto out_unref;
kmap_offset = dev_offset - bo->vm_node->start;
if (unlikely(kmap_offset >= bo->num_pages)) {
ret = -EFBIG;
goto out_unref;
}
page_offset = *f_pos & ~PAGE_MASK;
io_size = bo->num_pages - kmap_offset;
io_size = (io_size << PAGE_SHIFT) - page_offset;
if (count < io_size)
io_size = count;
kmap_end = (*f_pos + count - 1) >> PAGE_SHIFT;
kmap_num = kmap_end - kmap_offset + 1;
ret = ttm_bo_reserve(bo, true, no_wait, false, 0);
switch (ret) {
case 0:
break;
case -EBUSY:
ret = -EAGAIN;
goto out_unref;
default:
goto out_unref;
}
ret = ttm_bo_kmap(bo, kmap_offset, kmap_num, &map);
if (unlikely(ret != 0)) {
ttm_bo_unreserve(bo);
goto out_unref;
}
virtual = ttm_kmap_obj_virtual(&map, &dummy);
virtual += page_offset;
if (write)
ret = copy_from_user(virtual, wbuf, io_size);
else
