On 3/31/22 21:58, Rob Clark wrote:
> On Thu, Mar 31, 2022 at 11:27 AM Dmitry Osipenko
> <dmitry.osipenko@xxxxxxxxxxxxx> wrote:
>>
>> On 3/30/22 23:47, Rob Clark wrote:
>>> From: Rob Clark <robdclark@xxxxxxxxxxxx>
>>>
>>> Combines duplicate vma lookup in the get_and_pin path.
>>>
>>> Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
>>> ---
>>> drivers/gpu/drm/msm/msm_gem.c | 50 ++++++++++++++++++-----------------
>>> 1 file changed, 26 insertions(+), 24 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
>>> index deafae6feaa8..218744a490a4 100644
>>> --- a/drivers/gpu/drm/msm/msm_gem.c
>>> +++ b/drivers/gpu/drm/msm/msm_gem.c
>>> @@ -376,39 +376,40 @@ put_iova_vmas(struct drm_gem_object *obj)
>>> }
>>> }
>>>
>>> -static int get_iova_locked(struct drm_gem_object *obj,
>>> - struct msm_gem_address_space *aspace, uint64_t *iova,
>>> +static struct msm_gem_vma *get_vma_locked(struct drm_gem_object *obj,
>>> + struct msm_gem_address_space *aspace,
>>> u64 range_start, u64 range_end)
>>> {
>>> struct msm_gem_vma *vma;
>>> - int ret = 0;
>>>
>>> GEM_WARN_ON(!msm_gem_is_locked(obj));
>>>
>>> vma = lookup_vma(obj, aspace);
>>>
>>> if (!vma) {
>>> + int ret;
>>> +
>>> vma = add_vma(obj, aspace);
>>> if (IS_ERR(vma))
>>> - return PTR_ERR(vma);
>>> + return vma;
>>>
>>> ret = msm_gem_init_vma(aspace, vma, obj->size,
>>> range_start, range_end);
>>> if (ret) {
>> You're allocation range_start -> range_end
>>
>>
>>> del_vma(vma);
>>> - return ret;
>>> + return ERR_PTR(ret);
>>> }
>>> + } else {
>>> + GEM_WARN_ON(vma->iova < range_start);
>>> + GEM_WARN_ON((vma->iova + obj->size) > range_end);
>>
>> and then comparing range_start -> range_start + obj->size, hence you're
>> assuming that range_end always equals to obj->size during the allocation.
>>
>> I'm not sure what is the idea here.. this looks inconsistent. I think
>> you wanted to write:
>>
>> GEM_WARN_ON(vma->iova < range_start);
>> GEM_WARN_ON(vma->iova + (vma->node.size << PAGE_SHIFT) > range_end);
>>
>> But is it really useful to check whether the new range is inside of the
>> old range? Shouldn't it be always a error to change the IOVA range
>> without reallocating vma?
>
> There are a few cases (for allocations for GMU) where the range is
> larger than the bo.. see a6xx_gmu_memory_alloc()
Ahh, I didn't read the code properly and see now why you're using the
obj->size. It's the range where you want to put the BO. Looks good then.
Reviewed-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>
