On Mon, Jul 8, 2013 at 4:45 AM, Patrik Jakobsson patrik.r.jakobsson@gmail.com wrote:
On Sun, Jul 7, 2013 at 8:58 PM, Rob Clark robdclark@gmail.com wrote:
Basically just extracting some code duplicated in gma500, omapdrm, udl, and upcoming msm driver.
Signed-off-by: Rob Clark robdclark@gmail.com
drivers/gpu/drm/drm_gem.c | 91 +++++++++++++++++++++++++++++++++++++++++++++++ include/drm/drmP.h | 4 +++ 2 files changed, 95 insertions(+)
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 443eeff..853dea6 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -406,6 +406,97 @@ int drm_gem_create_mmap_offset(struct drm_gem_object *obj) } EXPORT_SYMBOL(drm_gem_create_mmap_offset);
+/**
- drm_gem_get_pages - helper to allocate backing pages for a GEM object
- from shmem
- @obj: obj in question
- @gfpmask: gfp mask of requested pages
- */
+struct page **drm_gem_get_pages(struct drm_gem_object *obj, gfp_t gfpmask) +{
struct inode *inode;struct address_space *mapping;struct page *p, **pages;int i, npages;/* This is the shared memory object that backs the GEM resource */inode = file_inode(obj->filp);mapping = inode->i_mapping;npages = obj->size >> PAGE_SHIFT;Theoretical issue, but what if obj->size is not page aligned? Perhaps put a roundup(obj->size, PAGE_SIZE) here?
so, drm_gem_object_init() does have:
BUG_ON((size & (PAGE_SIZE - 1)) != 0);
so I was kinda assuming that we can count on the size already being aligned. But I guess in case someone somehow bypasses drm_gem_object_init() it wouldn't hurt to round up the size..
BR, -R
pages = drm_malloc_ab(npages, sizeof(struct page *));if (pages == NULL)return ERR_PTR(-ENOMEM);gfpmask |= mapping_gfp_mask(mapping);for (i = 0; i < npages; i++) {p = shmem_read_mapping_page_gfp(mapping, i, gfpmask);if (IS_ERR(p))goto fail;pages[i] = p;/* There is a hypothetical issue w/ drivers that require* buffer memory in the low 4GB.. if the pages are un-* pinned, and swapped out, they can end up swapped back* in above 4GB. If pages are already in memory, then* shmem_read_mapping_page_gfp will ignore the gfpmask,* even if the already in-memory page disobeys the mask.** It is only a theoretical issue today, because none of* the devices with this limitation can be populated with* enough memory to trigger the issue. But this BUG_ON()* is here as a reminder in case the problem with* shmem_read_mapping_page_gfp() isn't solved by the time* it does become a real issue.** See this thread: http://lkml.org/lkml/2011/7/11/238*/BUG_ON((gfpmask & __GFP_DMA32) &&(page_to_pfn(p) >= 0x00100000UL));}return pages;+fail:
while (i--)page_cache_release(pages[i]);drm_free_large(pages);return ERR_CAST(p);+} +EXPORT_SYMBOL(drm_gem_get_pages);
+/**
- drm_gem_put_pages - helper to free backing pages for a GEM object
- @obj: obj in question
- @pages: pages to free
- @dirty: if true, pages will be marked as dirty
- @accessed: if true, the pages will be marked as accessed
- */
+void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
bool dirty, bool accessed)+{
int i, npages;npages = obj->size >> PAGE_SHIFT;Same thing here.
for (i = 0; i < npages; i++) {if (dirty)set_page_dirty(pages[i]);if (accessed)mark_page_accessed(pages[i]);/* Undo the reference we took when populating the table */page_cache_release(pages[i]);}drm_free_large(pages);+} +EXPORT_SYMBOL(drm_gem_put_pages);
/** Returns a reference to the object named by the handle. */ struct drm_gem_object * drm_gem_object_lookup(struct drm_device *dev, struct drm_file *filp, diff --git a/include/drm/drmP.h b/include/drm/drmP.h index 3cb1672..7ec3fa4 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -1730,6 +1730,10 @@ void drm_gem_free_mmap_offset(struct drm_gem_object *obj); int drm_gem_create_mmap_offset(struct drm_gem_object *obj); int drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size);
+struct page **drm_gem_get_pages(struct drm_gem_object *obj, gfp_t gfpmask); +void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
bool dirty, bool accessed);struct drm_gem_object *drm_gem_object_lookup(struct drm_device *dev, struct drm_file *filp, u32 handle); -- 1.8.1.4
Looks good otherwise, so for all 5 patches: Reviewed-by: Patrik Jakobsson patrik.r.jakobsson@gmail.com