[v11,01/10] drm/shmem-helper: Factor out pages alloc/release from drm_gem_shmem_get/put_pages()
Commit Message
Factor out pages allocation from drm_gem_shmem_get_pages() into
drm_gem_shmem_acquire_pages() function and similar for the put_pages()
in a preparation for addition of shrinker support to drm-shmem.
Once shrinker will be added, the pages_use_count>0 will no longer determine
whether pages are pinned because pages could be swapped out by the shrinker
and then pages_use_count will be greater than 0 in this case. We will add
new pages_pin_count in a later patch.
The new common drm_gem_shmem_acquire/release_pages() will be used by
shrinker code for performing the page swapping.
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
---
drivers/gpu/drm/drm_gem_shmem_helper.c | 67 +++++++++++++++++++++-----
1 file changed, 54 insertions(+), 13 deletions(-)
@@ -165,19 +165,26 @@ void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem)
}
EXPORT_SYMBOL_GPL(drm_gem_shmem_free);
-static int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem)
+static int
+drm_gem_shmem_acquire_pages(struct drm_gem_shmem_object *shmem)
{
struct drm_gem_object *obj = &shmem->base;
struct page **pages;
- if (shmem->pages_use_count++ > 0)
- return 0;
+ dma_resv_assert_held(shmem->base.resv);
+
+ if (shmem->madv < 0) {
+ drm_WARN_ON(obj->dev, shmem->pages);
+ return -ENOMEM;
+ }
+
+ if (drm_WARN_ON(obj->dev, !shmem->pages_use_count))
+ return -EINVAL;
pages = drm_gem_get_pages(obj);
if (IS_ERR(pages)) {
drm_dbg_kms(obj->dev, "Failed to get pages (%ld)\n",
PTR_ERR(pages));
- shmem->pages_use_count = 0;
return PTR_ERR(pages);
}
@@ -196,6 +203,48 @@ static int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem)
return 0;
}
+static int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem)
+{
+ int err;
+
+ dma_resv_assert_held(shmem->base.resv);
+
+ if (shmem->madv < 0)
+ return -ENOMEM;
+
+ if (shmem->pages_use_count++ > 0)
+ return 0;
+
+ err = drm_gem_shmem_acquire_pages(shmem);
+ if (err)
+ goto err_zero_use;
+
+ return 0;
+
+err_zero_use:
+ shmem->pages_use_count = 0;
+
+ return err;
+}
+
+static void
+drm_gem_shmem_release_pages(struct drm_gem_shmem_object *shmem)
+{
+ struct drm_gem_object *obj = &shmem->base;
+
+ dma_resv_assert_held(shmem->base.resv);
+
+#ifdef CONFIG_X86
+ if (shmem->map_wc)
+ set_pages_array_wb(shmem->pages, obj->size >> PAGE_SHIFT);
+#endif
+
+ drm_gem_put_pages(obj, shmem->pages,
+ shmem->pages_mark_dirty_on_put,
+ shmem->pages_mark_accessed_on_put);
+ shmem->pages = NULL;
+}
+
/*
* drm_gem_shmem_put_pages - Decrease use count on the backing pages for a shmem GEM object
* @shmem: shmem GEM object
@@ -214,15 +263,7 @@ void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem)
if (--shmem->pages_use_count > 0)
return;
-#ifdef CONFIG_X86
- if (shmem->map_wc)
- set_pages_array_wb(shmem->pages, obj->size >> PAGE_SHIFT);
-#endif
-
- drm_gem_put_pages(obj, shmem->pages,
- shmem->pages_mark_dirty_on_put,
- shmem->pages_mark_accessed_on_put);
- shmem->pages = NULL;
+ drm_gem_shmem_release_pages(shmem);
}
EXPORT_SYMBOL(drm_gem_shmem_put_pages);