drivers/gpu/drm/i915/i915_gemfs.c

   1 /*
   2  * Copyright © 2017 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  *
  23  */
  24
  25 #include <linux/fs.h>
  26 #include <linux/mount.h>
  27 #include <linux/pagemap.h>
  28
  29 #include "i915_drv.h"
  30 #include "i915_gemfs.h"
  31
  32 int i915_gemfs_init(struct drm_i915_private *i915)
  33 {
  34         struct file_system_type *type;
  35         struct vfsmount *gemfs;
  36
  37         type = get_fs_type("tmpfs");
  38         if (!type)
  39                 return -ENODEV;
  40
  41         gemfs = kern_mount(type);
  42         if (IS_ERR(gemfs))
  43                 return PTR_ERR(gemfs);
  44
  45         /*
  46          * Enable huge-pages for objects that are at least HPAGE_PMD_SIZE, most
  47          * likely 2M. Note that within_size may overallocate huge-pages, if say
  48          * we allocate an object of size 2M + 4K, we may get 2M + 2M, but under
  49          * memory pressure shmem should split any huge-pages which can be
  50          * shrunk.
  51          */
  52
  53         if (has_transparent_hugepage()) {
  54                 struct super_block *sb = gemfs->mnt_sb;
  55                 /* FIXME: Disabled until we get W/A for read BW issue. */
  56                 char options[] = "huge=never";
  57                 int flags = 0;
  58                 int err;
  59
  60                 err = sb->s_op->remount_fs(sb, &flags, options);
  61                 if (err) {
  62                         kern_unmount(gemfs);
  63                         return err;
  64                 }
  65         }
  66
  67         i915->mm.gemfs = gemfs;
  68
  69         return 0;
  70 }
  71
  72 void i915_gemfs_fini(struct drm_i915_private *i915)
  73 {
  74         kern_unmount(i915->mm.gemfs);
  75 }