1 // SPDX-License-Identifier: GPL-2.0+ 2 /* Copyright (C) 2024 Raspberry Pi */ 3 4 #include <linux/fs.h> 5 #include <linux/mount.h> 6 #include <linux/fs_context.h> 7 8 #include "v3d_drv.h" 9 v3d_gemfs_init(struct v3d_dev * v3d)10void v3d_gemfs_init(struct v3d_dev *v3d) 11 { 12 struct file_system_type *type; 13 struct fs_context *fc; 14 struct vfsmount *gemfs; 15 int ret; 16 17 /* 18 * By creating our own shmemfs mountpoint, we can pass in 19 * mount flags that better match our usecase. However, we 20 * only do so on platforms which benefit from it. 21 */ 22 if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) 23 goto err; 24 25 /* The user doesn't want to enable Super Pages */ 26 if (!super_pages) 27 goto err; 28 29 type = get_fs_type("tmpfs"); 30 if (!type) 31 goto err; 32 33 fc = fs_context_for_mount(type, SB_KERNMOUNT); 34 if (IS_ERR(fc)) 35 goto err; 36 ret = vfs_parse_fs_string(fc, "source", "tmpfs"); 37 if (!ret) 38 ret = vfs_parse_fs_string(fc, "huge", "within_size"); 39 if (!ret) 40 gemfs = fc_mount_longterm(fc); 41 put_fs_context(fc); 42 if (ret) 43 goto err; 44 45 v3d->gemfs = gemfs; 46 drm_info(&v3d->drm, "Using Transparent Hugepages\n"); 47 48 return; 49 50 err: 51 v3d->gemfs = NULL; 52 drm_notice(&v3d->drm, 53 "Transparent Hugepage support is recommended for optimal performance on this platform!\n"); 54 } 55 v3d_gemfs_fini(struct v3d_dev * v3d)56void v3d_gemfs_fini(struct v3d_dev *v3d) 57 { 58 if (v3d->gemfs) 59 kern_unmount(v3d->gemfs); 60 } 61