[Intel-gfx] [PATCH v2 1/2] drm/i915: Add i915_gem_object_vmap to map GEM object to virtual space
Tvrtko Ursulin
tvrtko.ursulin at linux.intel.com
Fri Feb 19 11:07:46 UTC 2016
On 18/02/16 18:31, yu.dai at intel.com wrote:
> From: Alex Dai <yu.dai at intel.com>
>
> There are several places inside driver where a GEM object is mapped to
> kernel virtual space. The mapping is either done for the whole object
> or certain page range of it.
>
> This patch introduces a function i915_gem_object_vmap to do such job.
>
> v2: Use obj->pages->nents for iteration within i915_gem_object_vmap;
> break when it finishes all desired pages. The caller need to pass
> in actual page number. (Tvrtko Ursulin)
Look OK to me. Just one more thing, it would be good to add a WARN_ON
and bail out if pages are not pinned. Just because the function is now
public and that is a bit stronger than kerneldoc.
With that added:
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
Regards,
Tvrtko
> Signed-off-by: Alex Dai <yu.dai at intel.com>
> Cc: Dave Gordon <david.s.gordon at intel.com>
> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
> Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Signed-off-by: Alex Dai <yu.dai at intel.com>
> ---
> drivers/gpu/drm/i915/i915_cmd_parser.c | 28 +-------------------
> drivers/gpu/drm/i915/i915_drv.h | 3 +++
> drivers/gpu/drm/i915/i915_gem.c | 47 +++++++++++++++++++++++++++++++++
> drivers/gpu/drm/i915/i915_gem_dmabuf.c | 16 +++--------
> drivers/gpu/drm/i915/intel_ringbuffer.c | 24 ++---------------
> 5 files changed, 56 insertions(+), 62 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_cmd_parser.c b/drivers/gpu/drm/i915/i915_cmd_parser.c
> index 814d894..915e8c1 100644
> --- a/drivers/gpu/drm/i915/i915_cmd_parser.c
> +++ b/drivers/gpu/drm/i915/i915_cmd_parser.c
> @@ -863,37 +863,11 @@ find_reg(const struct drm_i915_reg_descriptor *table,
> static u32 *vmap_batch(struct drm_i915_gem_object *obj,
> unsigned start, unsigned len)
> {
> - int i;
> - void *addr = NULL;
> - struct sg_page_iter sg_iter;
> int first_page = start >> PAGE_SHIFT;
> int last_page = (len + start + 4095) >> PAGE_SHIFT;
> int npages = last_page - first_page;
> - struct page **pages;
> -
> - pages = drm_malloc_ab(npages, sizeof(*pages));
> - if (pages == NULL) {
> - DRM_DEBUG_DRIVER("Failed to get space for pages\n");
> - goto finish;
> - }
> -
> - i = 0;
> - for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, first_page) {
> - pages[i++] = sg_page_iter_page(&sg_iter);
> - if (i == npages)
> - break;
> - }
> -
> - addr = vmap(pages, i, 0, PAGE_KERNEL);
> - if (addr == NULL) {
> - DRM_DEBUG_DRIVER("Failed to vmap pages\n");
> - goto finish;
> - }
>
> -finish:
> - if (pages)
> - drm_free_large(pages);
> - return (u32*)addr;
> + return (u32*)i915_gem_object_vmap(obj, first_page, npages);
> }
>
> /* Returns a vmap'd pointer to dest_obj, which the caller must unmap */
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 6644c2e..5b00a6a 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -2899,6 +2899,9 @@ struct drm_i915_gem_object *i915_gem_object_create_from_data(
> struct drm_device *dev, const void *data, size_t size);
> void i915_gem_free_object(struct drm_gem_object *obj);
> void i915_gem_vma_destroy(struct i915_vma *vma);
> +void *i915_gem_object_vmap(struct drm_i915_gem_object *obj,
> + unsigned int first,
> + unsigned int npages);
>
> /* Flags used by pin/bind&friends. */
> #define PIN_MAPPABLE (1<<0)
> diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
> index f68f346..4bc0ce7 100644
> --- a/drivers/gpu/drm/i915/i915_gem.c
> +++ b/drivers/gpu/drm/i915/i915_gem.c
> @@ -5356,3 +5356,50 @@ fail:
> drm_gem_object_unreference(&obj->base);
> return ERR_PTR(ret);
> }
> +
> +/**
> + * i915_gem_object_vmap - map a GEM obj into kernel virtual space
> + * @obj: the GEM obj to be mapped
> + * @first: index of the first page where mapping starts
> + * @npages: how many pages to be mapped, starting from first page
> + *
> + * Map a given page range of GEM obj into kernel virtual space. The caller must
> + * make sure the associated pages are gathered and pinned before calling this
> + * function. vunmap should be called after use.
> + *
> + * NULL will be returned if fails.
> + */
> +void *i915_gem_object_vmap(struct drm_i915_gem_object *obj,
> + unsigned int first,
> + unsigned int npages)
> +{
> + struct sg_page_iter sg_iter;
> + struct page **pages;
> + void *addr;
> + int i;
> +
> + if (first + npages > obj->pages->nents) {
> + DRM_DEBUG_DRIVER("Invalid page count\n");
> + return NULL;
> + }
> +
> + pages = drm_malloc_ab(npages, sizeof(*pages));
> + if (pages == NULL) {
> + DRM_DEBUG_DRIVER("Failed to get space for pages\n");
> + return NULL;
> + }
> +
> + i = 0;
> + for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, first) {
> + pages[i++] = sg_page_iter_page(&sg_iter);
> + if (i == npages)
> + break;
> + }
> +
> + addr = vmap(pages, npages, 0, PAGE_KERNEL);
> + if (addr == NULL)
> + DRM_DEBUG_DRIVER("Failed to vmap pages\n");
> + drm_free_large(pages);
> +
> + return addr;
> +}
> diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> index 1f3eef6..6133036 100644
> --- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> +++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
> @@ -110,9 +110,7 @@ static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
> {
> struct drm_i915_gem_object *obj = dma_buf_to_obj(dma_buf);
> struct drm_device *dev = obj->base.dev;
> - struct sg_page_iter sg_iter;
> - struct page **pages;
> - int ret, i;
> + int ret;
>
> ret = i915_mutex_lock_interruptible(dev);
> if (ret)
> @@ -131,16 +129,8 @@ static void *i915_gem_dmabuf_vmap(struct dma_buf *dma_buf)
>
> ret = -ENOMEM;
>
> - pages = drm_malloc_ab(obj->base.size >> PAGE_SHIFT, sizeof(*pages));
> - if (pages == NULL)
> - goto err_unpin;
> -
> - i = 0;
> - for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, 0)
> - pages[i++] = sg_page_iter_page(&sg_iter);
> -
> - obj->dma_buf_vmapping = vmap(pages, i, 0, PAGE_KERNEL);
> - drm_free_large(pages);
> + obj->dma_buf_vmapping = i915_gem_object_vmap(obj, 0,
> + dma_buf->size >> PAGE_SHIFT);
>
> if (!obj->dma_buf_vmapping)
> goto err_unpin;
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
> index 45ce45a..93666e9 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.c
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
> @@ -2064,27 +2064,6 @@ void intel_unpin_ringbuffer_obj(struct intel_ringbuffer *ringbuf)
> i915_gem_object_ggtt_unpin(ringbuf->obj);
> }
>
> -static u32 *vmap_obj(struct drm_i915_gem_object *obj)
> -{
> - struct sg_page_iter sg_iter;
> - struct page **pages;
> - void *addr;
> - int i;
> -
> - pages = drm_malloc_ab(obj->base.size >> PAGE_SHIFT, sizeof(*pages));
> - if (pages == NULL)
> - return NULL;
> -
> - i = 0;
> - for_each_sg_page(obj->pages->sgl, &sg_iter, obj->pages->nents, 0)
> - pages[i++] = sg_page_iter_page(&sg_iter);
> -
> - addr = vmap(pages, i, 0, PAGE_KERNEL);
> - drm_free_large(pages);
> -
> - return addr;
> -}
> -
> int intel_pin_and_map_ringbuffer_obj(struct drm_device *dev,
> struct intel_ringbuffer *ringbuf)
> {
> @@ -2103,7 +2082,8 @@ int intel_pin_and_map_ringbuffer_obj(struct drm_device *dev,
> return ret;
> }
>
> - ringbuf->virtual_start = vmap_obj(obj);
> + ringbuf->virtual_start = i915_gem_object_vmap(obj, 0,
> + ringbuf->size >> PAGE_SHIFT);
> if (ringbuf->virtual_start == NULL) {
> i915_gem_object_ggtt_unpin(obj);
> return -ENOMEM;
>
More information about the Intel-gfx
mailing list