Re: [PATCH 4/9] drm/ttm: Allow the driver to provide the ttm struct vm_operations_struct

From: Thomas Hellstrom
Date: Wed Apr 24 2019 - 10:20:42 EST


On Wed, 2019-04-24 at 14:10 +0000, Koenig, Christian wrote:
> Am 24.04.19 um 14:00 schrieb Thomas Hellstrom:
> > Add a pointer to the struct vm_operations_struct in the bo_device,
> > and
> > assign that pointer to the default value currently used.
> >
> > The driver can then optionally modify that pointer and the new
> > value
> > can be used for each new vma created.
> >
> > Cc: "Christian KÃnig" <christian.koenig@xxxxxxx>
> >
> > Signed-off-by: Thomas Hellstrom <thellstrom@xxxxxxxxxx>
> > Reviewed-by: Christian KÃnig <christian.koenig@xxxxxxx>
>
> Going to pick those two TTM patches up for amd-staging-drm-next.

Will you be relying on either patch for related work? Otherwise it
would be simpler for us to use vmwgfx-next for the whole series,
targeting 5.3.

Thomas

>
> Christian.
>
> > ---
> > drivers/gpu/drm/ttm/ttm_bo.c | 1 +
> > drivers/gpu/drm/ttm/ttm_bo_vm.c | 6 +++---
> > include/drm/ttm/ttm_bo_driver.h | 6 ++++++
> > 3 files changed, 10 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/ttm/ttm_bo.c
> > b/drivers/gpu/drm/ttm/ttm_bo.c
> > index 3f56647cdb35..1c85bec00472 100644
> > --- a/drivers/gpu/drm/ttm/ttm_bo.c
> > +++ b/drivers/gpu/drm/ttm/ttm_bo.c
> > @@ -1656,6 +1656,7 @@ int ttm_bo_device_init(struct ttm_bo_device
> > *bdev,
> > mutex_lock(&ttm_global_mutex);
> > list_add_tail(&bdev->device_list, &glob->device_list);
> > mutex_unlock(&ttm_global_mutex);
> > + bdev->vm_ops = &ttm_bo_vm_ops;
> >
> > return 0;
> > out_no_sys:
> > diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c
> > b/drivers/gpu/drm/ttm/ttm_bo_vm.c
> > index e86a29a1e51f..bfb25b81fed7 100644
> > --- a/drivers/gpu/drm/ttm/ttm_bo_vm.c
> > +++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c
> > @@ -395,7 +395,7 @@ static int ttm_bo_vm_access(struct
> > vm_area_struct *vma, unsigned long addr,
> > return ret;
> > }
> >
> > -static const struct vm_operations_struct ttm_bo_vm_ops = {
> > +const struct vm_operations_struct ttm_bo_vm_ops = {
> > .fault = ttm_bo_vm_fault,
> > .open = ttm_bo_vm_open,
> > .close = ttm_bo_vm_close,
> > @@ -445,7 +445,7 @@ int ttm_bo_mmap(struct file *filp, struct
> > vm_area_struct *vma,
> > if (unlikely(ret != 0))
> > goto out_unref;
> >
> > - vma->vm_ops = &ttm_bo_vm_ops;
> > + vma->vm_ops = bdev->vm_ops;
> >
> > /*
> > * Note: We're transferring the bo reference to
> > @@ -477,7 +477,7 @@ int ttm_fbdev_mmap(struct vm_area_struct *vma,
> > struct ttm_buffer_object *bo)
> >
> > ttm_bo_get(bo);
> >
> > - vma->vm_ops = &ttm_bo_vm_ops;
> > + vma->vm_ops = bo->bdev->vm_ops;
> > vma->vm_private_data = bo;
> > vma->vm_flags |= VM_MIXEDMAP;
> > vma->vm_flags |= VM_IO | VM_DONTEXPAND;
> > diff --git a/include/drm/ttm/ttm_bo_driver.h
> > b/include/drm/ttm/ttm_bo_driver.h
> > index cbf3180cb612..cfeaff5d9706 100644
> > --- a/include/drm/ttm/ttm_bo_driver.h
> > +++ b/include/drm/ttm/ttm_bo_driver.h
> > @@ -443,6 +443,9 @@ extern struct ttm_bo_global {
> > * @driver: Pointer to a struct ttm_bo_driver struct setup by the
> > driver.
> > * @man: An array of mem_type_managers.
> > * @vma_manager: Address space manager
> > + * @vm_ops: Pointer to the struct vm_operations_struct used for
> > this
> > + * device's VM operations. The driver may override this before the
> > first
> > + * mmap() call.
> > * lru_lock: Spinlock that protects the buffer+device lru lists
> > and
> > * ddestroy lists.
> > * @dev_mapping: A pointer to the struct address_space
> > representing the
> > @@ -461,6 +464,7 @@ struct ttm_bo_device {
> > struct ttm_bo_global *glob;
> > struct ttm_bo_driver *driver;
> > struct ttm_mem_type_manager man[TTM_NUM_MEM_TYPES];
> > + const struct vm_operations_struct *vm_ops;
> >
> > /*
> > * Protected by internal locks.
> > @@ -489,6 +493,8 @@ struct ttm_bo_device {
> > bool no_retry;
> > };
> >
> > +extern const struct vm_operations_struct ttm_bo_vm_ops;
> > +
> > /**
> > * struct ttm_lru_bulk_move_pos
> > *