Re: [PATCH] Remove custom dumb_map_offset implementations in i915 driver

From: Tvrtko Ursulin
Date: Fri Nov 10 2023 - 14:20:35 EST



On 10/11/2023 10:58, Dipam Turkar wrote:
Making i915 use drm_gem_create_mmap_offset() instead of its custom
implementations for associating GEM object with a fake offset.

Does it compile?

Regards,

Tvrtko

Signed-off-by: Dipam Turkar <dipamt1729@xxxxxxxxx>
---
drivers/gpu/drm/i915/gem/i915_gem_mman.c | 192 -----------------------
drivers/gpu/drm/i915/gem/i915_gem_mman.h | 4 -
drivers/gpu/drm/i915/i915_driver.c | 3 +-
3 files changed, 2 insertions(+), 197 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
index aa4d842d4c5a..6b73fe509270 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.c
@@ -600,198 +600,6 @@ void i915_gem_object_release_mmap_offset(struct drm_i915_gem_object *obj)
spin_unlock(&obj->mmo.lock);
}
-static struct i915_mmap_offset *
-lookup_mmo(struct drm_i915_gem_object *obj,
- enum i915_mmap_type mmap_type)
-{
- struct rb_node *rb;
-
- spin_lock(&obj->mmo.lock);
- rb = obj->mmo.offsets.rb_node;
- while (rb) {
- struct i915_mmap_offset *mmo =
- rb_entry(rb, typeof(*mmo), offset);
-
- if (mmo->mmap_type == mmap_type) {
- spin_unlock(&obj->mmo.lock);
- return mmo;
- }
-
- if (mmo->mmap_type < mmap_type)
- rb = rb->rb_right;
- else
- rb = rb->rb_left;
- }
- spin_unlock(&obj->mmo.lock);
-
- return NULL;
-}
-
-static struct i915_mmap_offset *
-insert_mmo(struct drm_i915_gem_object *obj, struct i915_mmap_offset *mmo)
-{
- struct rb_node *rb, **p;
-
- spin_lock(&obj->mmo.lock);
- rb = NULL;
- p = &obj->mmo.offsets.rb_node;
- while (*p) {
- struct i915_mmap_offset *pos;
-
- rb = *p;
- pos = rb_entry(rb, typeof(*pos), offset);
-
- if (pos->mmap_type == mmo->mmap_type) {
- spin_unlock(&obj->mmo.lock);
- drm_vma_offset_remove(obj->base.dev->vma_offset_manager,
- &mmo->vma_node);
- kfree(mmo);
- return pos;
- }
-
- if (pos->mmap_type < mmo->mmap_type)
- p = &rb->rb_right;
- else
- p = &rb->rb_left;
- }
- rb_link_node(&mmo->offset, rb, p);
- rb_insert_color(&mmo->offset, &obj->mmo.offsets);
- spin_unlock(&obj->mmo.lock);
-
- return mmo;
-}
-
-static struct i915_mmap_offset *
-mmap_offset_attach(struct drm_i915_gem_object *obj,
- enum i915_mmap_type mmap_type,
- struct drm_file *file)
-{
- struct drm_i915_private *i915 = to_i915(obj->base.dev);
- struct i915_mmap_offset *mmo;
- int err;
-
- GEM_BUG_ON(obj->ops->mmap_offset || obj->ops->mmap_ops);
-
- mmo = lookup_mmo(obj, mmap_type);
- if (mmo)
- goto out;
-
- mmo = kmalloc(sizeof(*mmo), GFP_KERNEL);
- if (!mmo)
- return ERR_PTR(-ENOMEM);
-
- mmo->obj = obj;
- mmo->mmap_type = mmap_type;
- drm_vma_node_reset(&mmo->vma_node);
-
- err = drm_vma_offset_add(obj->base.dev->vma_offset_manager,
- &mmo->vma_node, obj->base.size / PAGE_SIZE);
- if (likely(!err))
- goto insert;
-
- /* Attempt to reap some mmap space from dead objects */
- err = intel_gt_retire_requests_timeout(to_gt(i915), MAX_SCHEDULE_TIMEOUT,
- NULL);
- if (err)
- goto err;
-
- i915_gem_drain_freed_objects(i915);
- err = drm_vma_offset_add(obj->base.dev->vma_offset_manager,
- &mmo->vma_node, obj->base.size / PAGE_SIZE);
- if (err)
- goto err;
-
-insert:
- mmo = insert_mmo(obj, mmo);
- GEM_BUG_ON(lookup_mmo(obj, mmap_type) != mmo);
-out:
- if (file)
- drm_vma_node_allow_once(&mmo->vma_node, file);
- return mmo;
-
-err:
- kfree(mmo);
- return ERR_PTR(err);
-}
-
-static int
-__assign_mmap_offset(struct drm_i915_gem_object *obj,
- enum i915_mmap_type mmap_type,
- u64 *offset, struct drm_file *file)
-{
- struct i915_mmap_offset *mmo;
-
- if (i915_gem_object_never_mmap(obj))
- return -ENODEV;
-
- if (obj->ops->mmap_offset) {
- if (mmap_type != I915_MMAP_TYPE_FIXED)
- return -ENODEV;
-
- *offset = obj->ops->mmap_offset(obj);
- return 0;
- }
-
- if (mmap_type == I915_MMAP_TYPE_FIXED)
- return -ENODEV;
-
- if (mmap_type != I915_MMAP_TYPE_GTT &&
- !i915_gem_object_has_struct_page(obj) &&
- !i915_gem_object_has_iomem(obj))
- return -ENODEV;
-
- mmo = mmap_offset_attach(obj, mmap_type, file);
- if (IS_ERR(mmo))
- return PTR_ERR(mmo);
-
- *offset = drm_vma_node_offset_addr(&mmo->vma_node);
- return 0;
-}
-
-static int
-__assign_mmap_offset_handle(struct drm_file *file,
- u32 handle,
- enum i915_mmap_type mmap_type,
- u64 *offset)
-{
- struct drm_i915_gem_object *obj;
- int err;
-
- obj = i915_gem_object_lookup(file, handle);
- if (!obj)
- return -ENOENT;
-
- err = i915_gem_object_lock_interruptible(obj, NULL);
- if (err)
- goto out_put;
- err = __assign_mmap_offset(obj, mmap_type, offset, file);
- i915_gem_object_unlock(obj);
-out_put:
- i915_gem_object_put(obj);
- return err;
-}
-
-int
-i915_gem_dumb_mmap_offset(struct drm_file *file,
- struct drm_device *dev,
- u32 handle,
- u64 *offset)
-{
- struct drm_i915_private *i915 = to_i915(dev);
- enum i915_mmap_type mmap_type;
-
- if (HAS_LMEM(to_i915(dev)))
- mmap_type = I915_MMAP_TYPE_FIXED;
- else if (pat_enabled())
- mmap_type = I915_MMAP_TYPE_WC;
- else if (!i915_ggtt_has_aperture(to_gt(i915)->ggtt))
- return -ENODEV;
- else
- mmap_type = I915_MMAP_TYPE_GTT;
-
- return __assign_mmap_offset_handle(file, handle, mmap_type, offset);
-}
-
/**
* i915_gem_mmap_offset_ioctl - prepare an object for GTT mmap'ing
* @dev: DRM device
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_mman.h b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
index 196417fd0f5c..253435795caf 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_mman.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_mman.h
@@ -20,10 +20,6 @@ struct mutex;
int i915_gem_mmap_gtt_version(void);
int i915_gem_mmap(struct file *filp, struct vm_area_struct *vma);
-int i915_gem_dumb_mmap_offset(struct drm_file *file_priv,
- struct drm_device *dev,
- u32 handle, u64 *offset);
-
void __i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
void i915_gem_object_release_mmap_gtt(struct drm_i915_gem_object *obj);
diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
index d50347e5773a..a18a33896ba4 100644
--- a/drivers/gpu/drm/i915/i915_driver.c
+++ b/drivers/gpu/drm/i915/i915_driver.c
@@ -42,6 +42,7 @@
#include <drm/drm_aperture.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_ioctl.h>
+#include <drm/drm_gem.h>
#include <drm/drm_managed.h>
#include <drm/drm_probe_helper.h>
@@ -1826,7 +1827,7 @@ static const struct drm_driver i915_drm_driver = {
.gem_prime_import = i915_gem_prime_import,
.dumb_create = i915_gem_dumb_create,
- .dumb_map_offset = i915_gem_dumb_mmap_offset,
+ .dumb_map_offset = drm_gem_dumb_mmap_offset,
.ioctls = i915_ioctls,
.num_ioctls = ARRAY_SIZE(i915_ioctls),