3 files changed, 70 insertions, 15 deletions

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_domain.c b/drivers/gpu/drm/i915/gem/i915_gem_domain.c
index 7c90a63c273d..fcce6909f201 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_domain.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_domain.c
@@ -509,21 +509,6 @@ i915_gem_set_domain_ioctl(struct drm_device *dev, void *data,
 		return -ENOENT;
 
 	/*
-	 * Already in the desired write domain? Nothing for us to do!
-	 *
-	 * We apply a little bit of cunning here to catch a broader set of
-	 * no-ops. If obj->write_domain is set, we must be in the same
-	 * obj->read_domains, and only that domain. Therefore, if that
-	 * obj->write_domain matches the request read_domains, we are
-	 * already in the same read/write domain and can skip the operation,
-	 * without having to further check the requested write_domain.
-	 */
-	if (READ_ONCE(obj->write_domain) == read_domains) {
-		err = 0;
-		goto out;
-	}
-
-	/*
 	 * Try to flush the object off the GPU without holding the lock.
 	 * We will repeat the flush holding the lock in the normal manner
 	 * to catch cases where we are gazumped.
@@ -560,6 +545,19 @@ i915_gem_set_domain_ioctl(struct drm_device *dev, void *data,
 	if (err)
 		goto out;
 
+	/*
+	 * Already in the desired write domain? Nothing for us to do!
+	 *
+	 * We apply a little bit of cunning here to catch a broader set of
+	 * no-ops. If obj->write_domain is set, we must be in the same
+	 * obj->read_domains, and only that domain. Therefore, if that
+	 * obj->write_domain matches the request read_domains, we are
+	 * already in the same read/write domain and can skip the operation,
+	 * without having to further check the requested write_domain.
+	 */
+	if (READ_ONCE(obj->write_domain) == read_domains)
+		goto out_unpin;
+
 	err = i915_gem_object_lock_interruptible(obj, NULL);
 	if (err)
 		goto out_unpin;
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
index b5c15557cc87..d6711caa7f39 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object_types.h
@@ -56,6 +56,8 @@ struct drm_i915_gem_object_ops {
 	void (*truncate)(struct drm_i915_gem_object *obj);
 	void (*writeback)(struct drm_i915_gem_object *obj);
 
+	int (*pread)(struct drm_i915_gem_object *obj,
+		     const struct drm_i915_gem_pread *arg);
 	int (*pwrite)(struct drm_i915_gem_object *obj,
 		      const struct drm_i915_gem_pwrite *arg);
 
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_phys.c b/drivers/gpu/drm/i915/gem/i915_gem_phys.c
index 28147aab47b9..3a4dfe2ef1da 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_phys.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_phys.c
@@ -134,6 +134,58 @@ i915_gem_object_put_pages_phys(struct drm_i915_gem_object *obj,
 			  vaddr, dma);
 }
 
+static int
+phys_pwrite(struct drm_i915_gem_object *obj,
+	    const struct drm_i915_gem_pwrite *args)
+{
+	void *vaddr = sg_page(obj->mm.pages->sgl) + args->offset;
+	char __user *user_data = u64_to_user_ptr(args->data_ptr);
+	int err;
+
+	err = i915_gem_object_wait(obj,
+				   I915_WAIT_INTERRUPTIBLE |
+				   I915_WAIT_ALL,
+				   MAX_SCHEDULE_TIMEOUT);
+	if (err)
+		return err;
+
+	/*
+	 * We manually control the domain here and pretend that it
+	 * remains coherent i.e. in the GTT domain, like shmem_pwrite.
+	 */
+	i915_gem_object_invalidate_frontbuffer(obj, ORIGIN_CPU);
+
+	if (copy_from_user(vaddr, user_data, args->size))
+		return -EFAULT;
+
+	drm_clflush_virt_range(vaddr, args->size);
+	intel_gt_chipset_flush(&to_i915(obj->base.dev)->gt);
+
+	i915_gem_object_flush_frontbuffer(obj, ORIGIN_CPU);
+	return 0;
+}
+
+static int
+phys_pread(struct drm_i915_gem_object *obj,
+	   const struct drm_i915_gem_pread *args)
+{
+	void *vaddr = sg_page(obj->mm.pages->sgl) + args->offset;
+	char __user *user_data = u64_to_user_ptr(args->data_ptr);
+	int err;
+
+	err = i915_gem_object_wait(obj,
+				   I915_WAIT_INTERRUPTIBLE,
+				   MAX_SCHEDULE_TIMEOUT);
+	if (err)
+		return err;
+
+	drm_clflush_virt_range(vaddr, args->size);
+	if (copy_to_user(user_data, vaddr, args->size))
+		return -EFAULT;
+
+	return 0;
+}
+
 static void phys_release(struct drm_i915_gem_object *obj)
 {
 	fput(obj->base.filp);
@@ -144,6 +196,9 @@ static const struct drm_i915_gem_object_ops i915_gem_phys_ops = {
 	.get_pages = i915_gem_object_get_pages_phys,
 	.put_pages = i915_gem_object_put_pages_phys,
 
+	.pread  = phys_pread,
+	.pwrite = phys_pwrite,
+
 	.release = phys_release,
 };