i915: add dmabuf/prime buffer sharing support.
This adds handle->fd and fd->handle support to i915, this is to allow
for offloading of rendering in one direction and outputs in the other.
v2 from Daniel Vetter:
- fixup conflicts with the prepare/finish gtt prep work.
- implement ppgtt binding support.
Note that we have squat i-g-t testcoverage for any of the lifetime and
access rules dma_buf/prime support brings along. And there are quite a
few intricate situations here.
Also note that the integration with the existing code is a bit
hackish, especially around get_gtt_pages and put_gtt_pages. It imo
would be easier with the prep code from Chris Wilson's unbound series,
but that is for 3.6.
Also note that I didn't bother to put the new prepare/finish gtt hooks
to good use by moving the dma_buf_map/unmap_attachment calls in there
(like we've originally planned for).
Last but not least this patch is only compile-tested, but I've changed
very little compared to Dave Airlie's version. So there's a decent
chance v2 on drm-next works as well as v1 on 3.4-rc.
v3: Right when I've hit sent I've noticed that I've screwed up one
obj->sg_list (for dmar support) and obj->sg_table (for prime support)
disdinction. We should be able to merge these 2 paths, but that's
material for another patch.
v4: fix the error reporting bugs pointed out by ickle.
v5: fix another error, and stop non-gtt mmaps on shared objects
stop pread/pwrite on imported objects, add fake kmap
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 6d2180c..c1e5c66 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -35,6 +35,7 @@
#include <linux/slab.h>
#include <linux/swap.h>
#include <linux/pci.h>
+#include <linux/dma-buf.h>
static __must_check int i915_gem_object_flush_gpu_write_domain(struct drm_i915_gem_object *obj);
static void i915_gem_object_flush_gtt_write_domain(struct drm_i915_gem_object *obj);
@@ -538,6 +539,14 @@
goto out;
}
+ /* prime objects have no backing filp to GEM pread/pwrite
+ * pages from.
+ */
+ if (!obj->base.filp) {
+ ret = -EINVAL;
+ goto out;
+ }
+
trace_i915_gem_object_pread(obj, args->offset, args->size);
ret = i915_gem_shmem_pread(dev, obj, args, file);
@@ -880,6 +889,14 @@
goto out;
}
+ /* prime objects have no backing filp to GEM pread/pwrite
+ * pages from.
+ */
+ if (!obj->base.filp) {
+ ret = -EINVAL;
+ goto out;
+ }
+
trace_i915_gem_object_pwrite(obj, args->offset, args->size);
ret = -EFAULT;
@@ -1021,6 +1038,14 @@
if (obj == NULL)
return -ENOENT;
+ /* prime objects have no backing filp to GEM mmap
+ * pages from.
+ */
+ if (!obj->filp) {
+ drm_gem_object_unreference_unlocked(obj);
+ return -EINVAL;
+ }
+
addr = vm_mmap(obj->filp, 0, args->size,
PROT_READ | PROT_WRITE, MAP_SHARED,
args->offset);
@@ -1302,8 +1327,7 @@
return i915_gem_mmap_gtt(file, dev, args->handle, &args->offset);
}
-
-static int
+int
i915_gem_object_get_pages_gtt(struct drm_i915_gem_object *obj,
gfp_t gfpmask)
{
@@ -1312,6 +1336,9 @@
struct inode *inode;
struct page *page;
+ if (obj->pages || obj->sg_table)
+ return 0;
+
/* Get the list of pages out of our struct file. They'll be pinned
* at this point until we release them.
*/
@@ -1353,6 +1380,9 @@
int page_count = obj->base.size / PAGE_SIZE;
int i;
+ if (!obj->pages)
+ return;
+
BUG_ON(obj->madv == __I915_MADV_PURGED);
if (i915_gem_object_needs_bit17_swizzle(obj))
@@ -3327,6 +3357,9 @@
trace_i915_gem_object_destroy(obj);
+ if (gem_obj->import_attach)
+ drm_prime_gem_destroy(gem_obj, obj->sg_table);
+
if (obj->phys_obj)
i915_gem_detach_phys_object(dev, obj);