[Intel-gfx] [PATCH 3/4] drm/i915: handle walking compact dma scatter lists
Imre Deak
imre.deak at intel.com
Sat Feb 9 14:59:04 PST 2013
On Sat, 2013-02-09 at 23:51 +0100, Daniel Vetter wrote:
> On Sat, Feb 09, 2013 at 05:27:35PM +0200, Imre Deak wrote:
> > So far the assumption was that each dma scatter list entry contains only
> > a single page. This might not hold in the future, when we'll introduce
> > compact scatter lists, so prepare for this everywhere in the i915 code
> > where we walk such a list.
> >
> > We'll fix the place _creating_ these lists separately in the next patch
> > to help the reviewing/bisectability.
> >
> > Reference: http://www.spinics.net/lists/dri-devel/msg33917.html
> > Signed-off-by: Imre Deak <imre.deak at intel.com>
>
> Since we now have such a nice macro to loop over sg pages ... Care to also
> convert the two existing (correct loops) in i915_gem_gtt.c and intel-gtt.c
> in a follow-up patch?
Ok, will do.
--Imre
> -Daniel
>
> > ---
> > drivers/gpu/drm/i915/i915_drv.h | 17 ++++++-----------
> > drivers/gpu/drm/i915/i915_gem.c | 22 ++++++----------------
> > drivers/gpu/drm/i915/i915_gem_dmabuf.c | 13 +++++++------
> > drivers/gpu/drm/i915/i915_gem_tiling.c | 18 ++++++++++--------
> > 4 files changed, 29 insertions(+), 41 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> > index 08c5def..0462428 100644
> > --- a/drivers/gpu/drm/i915/i915_drv.h
> > +++ b/drivers/gpu/drm/i915/i915_drv.h
> > @@ -1531,17 +1531,12 @@ void i915_gem_lastclose(struct drm_device *dev);
> > int __must_check i915_gem_object_get_pages(struct drm_i915_gem_object *obj);
> > static inline struct page *i915_gem_object_get_page(struct drm_i915_gem_object *obj, int n)
> > {
> > - struct scatterlist *sg = obj->pages->sgl;
> > - int nents = obj->pages->nents;
> > - while (nents > SG_MAX_SINGLE_ALLOC) {
> > - if (n < SG_MAX_SINGLE_ALLOC - 1)
> > - break;
> > -
> > - sg = sg_chain_ptr(sg + SG_MAX_SINGLE_ALLOC - 1);
> > - n -= SG_MAX_SINGLE_ALLOC - 1;
> > - nents -= SG_MAX_SINGLE_ALLOC - 1;
> > - }
> > - return sg_page(sg+n);
> > + struct drm_sg_iter sg_iter;
> > +
> > + drm_for_each_sg_page(&sg_iter, obj->pages->sgl, n << PAGE_SHIFT)
> > + return sg_iter.page;
> > +
> > + return NULL;
> > }
> > static inline void i915_gem_object_pin_pages(struct drm_i915_gem_object *obj)
> > {
> > diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> > index d746177..4a199e0 100644
> > --- a/drivers/gpu/drm/i915/i915_gem.c
> > +++ b/drivers/gpu/drm/i915/i915_gem.c
> > @@ -411,8 +411,7 @@ i915_gem_shmem_pread(struct drm_device *dev,
> > int obj_do_bit17_swizzling, page_do_bit17_swizzling;
> > int prefaulted = 0;
> > int needs_clflush = 0;
> > - struct scatterlist *sg;
> > - int i;
> > + struct drm_sg_iter sg_iter;
> >
> > user_data = (char __user *) (uintptr_t) args->data_ptr;
> > remain = args->size;
> > @@ -441,11 +440,8 @@ i915_gem_shmem_pread(struct drm_device *dev,
> >
> > offset = args->offset;
> >
> > - for_each_sg(obj->pages->sgl, sg, obj->pages->nents, i) {
> > - struct page *page;
> > -
> > - if (i < offset >> PAGE_SHIFT)
> > - continue;
> > + drm_for_each_sg_page(&sg_iter, obj->pages->sgl, offset) {
> > + struct page *page = sg_iter.page;
> >
> > if (remain <= 0)
> > break;
> > @@ -460,7 +456,6 @@ i915_gem_shmem_pread(struct drm_device *dev,
> > if ((shmem_page_offset + page_length) > PAGE_SIZE)
> > page_length = PAGE_SIZE - shmem_page_offset;
> >
> > - page = sg_page(sg);
> > page_do_bit17_swizzling = obj_do_bit17_swizzling &&
> > (page_to_phys(page) & (1 << 17)) != 0;
> >
> > @@ -732,8 +727,7 @@ i915_gem_shmem_pwrite(struct drm_device *dev,
> > int hit_slowpath = 0;
> > int needs_clflush_after = 0;
> > int needs_clflush_before = 0;
> > - int i;
> > - struct scatterlist *sg;
> > + struct drm_sg_iter sg_iter;
> >
> > user_data = (char __user *) (uintptr_t) args->data_ptr;
> > remain = args->size;
> > @@ -768,13 +762,10 @@ i915_gem_shmem_pwrite(struct drm_device *dev,
> > offset = args->offset;
> > obj->dirty = 1;
> >
> > - for_each_sg(obj->pages->sgl, sg, obj->pages->nents, i) {
> > - struct page *page;
> > + drm_for_each_sg_page(&sg_iter, obj->pages->sgl, offset) {
> > + struct page *page = sg_iter.page;
> > int partial_cacheline_write;
> >
> > - if (i < offset >> PAGE_SHIFT)
> > - continue;
> > -
> > if (remain <= 0)
> > break;
> >
> > @@ -796,7 +787,6 @@ i915_gem_shmem_pwrite(struct drm_device *dev,
> > ((shmem_page_offset | page_length)
> > & (boot_cpu_data.x86_clflush_size - 1));
> >
> > - page = sg_page(sg);
> > page_do_bit17_swizzling = obj_do_bit17_swizzling &&
> > (page_to_phys(page) & (1 << 17)) != 0;
> >
> > diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> > index 6a5af68..ac98792 100644
> > --- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> > +++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> > @@ -62,7 +62,7 @@ static struct sg_table *i915_gem_map_dma_buf(struct dma_buf_attachment *attachme
> > src = obj->pages->sgl;
> > dst = st->sgl;
> > for (i = 0; i < obj->pages->nents; i++) {
> > - sg_set_page(dst, sg_page(src), PAGE_SIZE, 0);
> > + sg_set_page(dst, sg_page(src), src->length, 0);
> > dst = sg_next(dst);
> > src = sg_next(src);
> > }
> > @@ -105,7 +105,7 @@ static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
> > {
> > struct drm_i915_gem_object *obj = dma_buf->priv;
> > struct drm_device *dev = obj->base.dev;
> > - struct scatterlist *sg;
> > + struct drm_sg_iter sg_iter;
> > struct page **pages;
> > int ret, i;
> >
> > @@ -124,14 +124,15 @@ static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
> >
> > ret = -ENOMEM;
> >
> > - pages = drm_malloc_ab(obj->pages->nents, sizeof(struct page *));
> > + pages = drm_malloc_ab(obj->base.size >> PAGE_SHIFT, sizeof(*pages));
> > if (pages == NULL)
> > goto error;
> >
> > - for_each_sg(obj->pages->sgl, sg, obj->pages->nents, i)
> > - pages[i] = sg_page(sg);
> > + i = 0;
> > + drm_for_each_sg_page(&sg_iter, obj->pages->sgl, 0);
> > + pages[i++] = sg_iter.page;
> >
> > - obj->dma_buf_vmapping = vmap(pages, obj->pages->nents, 0, PAGE_KERNEL);
> > + obj->dma_buf_vmapping = vmap(pages, i, 0, PAGE_KERNEL);
> > drm_free_large(pages);
> >
> > if (!obj->dma_buf_vmapping)
> > diff --git a/drivers/gpu/drm/i915/i915_gem_tiling.c b/drivers/gpu/drm/i915/i915_gem_tiling.c
> > index abcba2f..834ed70 100644
> > --- a/drivers/gpu/drm/i915/i915_gem_tiling.c
> > +++ b/drivers/gpu/drm/i915/i915_gem_tiling.c
> > @@ -473,28 +473,29 @@ i915_gem_swizzle_page(struct page *page)
> > void
> > i915_gem_object_do_bit_17_swizzle(struct drm_i915_gem_object *obj)
> > {
> > - struct scatterlist *sg;
> > - int page_count = obj->base.size >> PAGE_SHIFT;
> > + struct drm_sg_iter sg_iter;
> > int i;
> >
> > if (obj->bit_17 == NULL)
> > return;
> >
> > - for_each_sg(obj->pages->sgl, sg, page_count, i) {
> > - struct page *page = sg_page(sg);
> > + i = 0;
> > + drm_for_each_sg_page(&sg_iter, obj->pages->sgl, 0) {
> > + struct page *page = sg_iter.page;
> > char new_bit_17 = page_to_phys(page) >> 17;
> > if ((new_bit_17 & 0x1) !=
> > (test_bit(i, obj->bit_17) != 0)) {
> > i915_gem_swizzle_page(page);
> > set_page_dirty(page);
> > }
> > + i++;
> > }
> > }
> >
> > void
> > i915_gem_object_save_bit_17_swizzle(struct drm_i915_gem_object *obj)
> > {
> > - struct scatterlist *sg;
> > + struct drm_sg_iter sg_iter;
> > int page_count = obj->base.size >> PAGE_SHIFT;
> > int i;
> >
> > @@ -508,11 +509,12 @@ i915_gem_object_save_bit_17_swizzle(struct drm_i915_gem_object *obj)
> > }
> > }
> >
> > - for_each_sg(obj->pages->sgl, sg, page_count, i) {
> > - struct page *page = sg_page(sg);
> > - if (page_to_phys(page) & (1 << 17))
> > + i = 0;
> > + drm_for_each_sg_page(&sg_iter, obj->pages->sgl, 0) {
> > + if (page_to_phys(sg_iter.page) & (1 << 17))
> > __set_bit(i, obj->bit_17);
> > else
> > __clear_bit(i, obj->bit_17);
> > + i++;
> > }
> > }
> > --
> > 1.7.10.4
> >
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx at lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
>
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