xref: /openbmc/linux/drivers/gpu/drm/i915/gem/i915_gemfs.c (revision d9fd5a71)
1 /*
2  * SPDX-License-Identifier: MIT
3  *
4  * Copyright © 2017 Intel Corporation
5  */
6 
7 #include <linux/fs.h>
8 #include <linux/mount.h>
9 #include <linux/pagemap.h>
10 
11 #include "i915_drv.h"
12 #include "i915_gemfs.h"
13 
14 int i915_gemfs_init(struct drm_i915_private *i915)
15 {
16 	struct file_system_type *type;
17 	struct vfsmount *gemfs;
18 
19 	type = get_fs_type("tmpfs");
20 	if (!type)
21 		return -ENODEV;
22 
23 	/*
24 	 * By creating our own shmemfs mountpoint, we can pass in
25 	 * mount flags that better match our usecase.
26 	 *
27 	 * One example, although it is probably better with a per-file
28 	 * control, is selecting huge page allocations ("huge=within_size").
29 	 * Currently unused due to bandwidth issues (slow reads) on Broadwell+.
30 	 */
31 
32 	gemfs = kern_mount(type);
33 	if (IS_ERR(gemfs))
34 		return PTR_ERR(gemfs);
35 
36 	i915->mm.gemfs = gemfs;
37 
38 	return 0;
39 }
40 
41 void i915_gemfs_fini(struct drm_i915_private *i915)
42 {
43 	kern_unmount(i915->mm.gemfs);
44 }
45