Attached is a patch for umr{master} which should in theory support both
iova and iomem.
I can add the write method if you want since ya it should be fairly
simple to copy/pasta that up.
Cheers,
Tom
On 05/02/18 07:07 AM, Christian König wrote:
> Well adding write support is trivial.
>
> What I'm more concerned about is if setting page->mapping during
> allocation of the page could have any negative effect?
>
> I of hand don't see any since the page isn't reclaimable directly
> anyway, but I'm not 100% sure of that.
>
> Christian.
>
> Am 05.02.2018 um 12:49 schrieb Tom St Denis:
>> Another thing that occurred to me is this will break write access to
>> GPU bound memory. Previously we relied on iova to translate the
>> address and then /dev/mem or /dev/fmem to read/write it. But since
>> this is literally a read only method obviously there's no write support.
>>
>> Tom
>>
>>
>> On 04/02/18 09:56 PM, He, Roger wrote:
>>> Patch1 & 2 & 4,  Reviewed-by: Roger He <Hongbo.He at amd.com>
>>> Patch 5:Â Acked-by: Roger He <Hongbo.He at amd.com>
>>>
>>> -----Original Message-----
>>> From: dri-devel [mailto:dri-devel-bounces at lists.freedesktop.org] On
>>> Behalf Of Christian K?nig
>>> Sent: Saturday, February 03, 2018 3:10 AM
>>> To: amd-gfx at lists.freedesktop.org; dri-devel at lists.freedesktop.org
>>> Subject: [PATCH 5/5] drm/amdgpu: replace iova debugfs file with iomem
>>>
>>> This allows access to pages allocated through the driver with
>>> optional IOMMU mapping.
>>>
>>> Signed-off-by: Christian König <christian.koenig at amd.com>
>>> ---
>>> Â drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 57
>>> ++++++++++++++++++++-------------
>>> Â 1 file changed, 35 insertions(+), 22 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>> index 648c449aaa79..795ceaeb82d5 100644
>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>> @@ -1929,38 +1929,51 @@ static const struct file_operations
>>> amdgpu_ttm_gtt_fops = {
>>> Â Â #endif
>>> Â -static ssize_t amdgpu_iova_to_phys_read(struct file *f, char
>>> __user *buf,
>>> -Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â size_t size, loff_t *pos)
>>> +static ssize_t amdgpu_iomem_read(struct file *f, char __user *buf,
>>> +Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â size_t size, loff_t *pos)
>>> Â {
>>> Â Â Â Â Â struct amdgpu_device *adev = file_inode(f)->i_private;
>>> -Â Â Â int r;
>>> -Â Â Â uint64_t phys;
>>> Â Â Â Â Â struct iommu_domain *dom;
>>> +Â Â Â ssize_t result = 0;
>>> +Â Â Â int r;
>>> Â -Â Â Â // always return 8 bytes
>>> -Â Â Â if (size != 8)
>>> -Â Â Â Â Â Â Â return -EINVAL;
>>> +Â Â Â dom = iommu_get_domain_for_dev(adev->dev);
>>> Â -Â Â Â // only accept page addresses
>>> -Â Â Â if (*pos & 0xFFF)
>>> -Â Â Â Â Â Â Â return -EINVAL;
>>> +Â Â Â while (size) {
>>> +Â Â Â Â Â Â Â phys_addr_t addr = *pos & PAGE_MASK;
>>> +Â Â Â Â Â Â Â loff_t off = *pos & ~PAGE_MASK;
>>> +Â Â Â Â Â Â Â size_t bytes = PAGE_SIZE - off;
>>> +Â Â Â Â Â Â Â unsigned long pfn;
>>> +Â Â Â Â Â Â Â struct page *p;
>>> +Â Â Â Â Â Â Â void *ptr;
>>> Â -Â Â Â dom = iommu_get_domain_for_dev(adev->dev);
>>> -Â Â Â if (dom)
>>> -Â Â Â Â Â Â Â phys = iommu_iova_to_phys(dom, *pos);
>>> -Â Â Â else
>>> -Â Â Â Â Â Â Â phys = *pos;
>>> +Â Â Â Â Â Â Â addr = dom ? iommu_iova_to_phys(dom, addr) : addr;
>>> Â -Â Â Â r = copy_to_user(buf, &phys, 8);
>>> -Â Â Â if (r)
>>> -Â Â Â Â Â Â Â return -EFAULT;
>>> +Â Â Â Â Â Â Â pfn = addr >> PAGE_SHIFT;
>>> +Â Â Â Â Â Â Â if (!pfn_valid(pfn))
>>> +Â Â Â Â Â Â Â Â Â Â Â return -EPERM;
>>> +
>>> +Â Â Â Â Â Â Â p = pfn_to_page(pfn);
>>> +Â Â Â Â Â Â Â if (p->mapping != adev->mman.bdev.dev_mapping)
>>> +Â Â Â Â Â Â Â Â Â Â Â return -EPERM;
>>> +
>>> +Â Â Â Â Â Â Â ptr = kmap(p);
>>> +Â Â Â Â Â Â Â r = copy_to_user(buf, ptr, bytes);
>>> +Â Â Â Â Â Â Â kunmap(p);
>>> +Â Â Â Â Â Â Â if (r)
>>> +Â Â Â Â Â Â Â Â Â Â Â return -EFAULT;
>>> Â -Â Â Â return 8;
>>> +Â Â Â Â Â Â Â size -= bytes;
>>> +Â Â Â Â Â Â Â *pos += bytes;
>>> +Â Â Â Â Â Â Â result += bytes;
>>> +Â Â Â }
>>> +
>>> +Â Â Â return result;
>>> Â }
>>> Â -static const struct file_operations amdgpu_ttm_iova_fops = {
>>> +static const struct file_operations amdgpu_ttm_iomem_fops = {
>>> Â Â Â Â Â .owner = THIS_MODULE,
>>> -Â Â Â .read = amdgpu_iova_to_phys_read,
>>> +Â Â Â .read = amdgpu_iomem_read,
>>> Â Â Â Â Â .llseek = default_llseek
>>> Â };
>>> Â @@ -1973,7 +1986,7 @@ static const struct {Â #ifdef
>>> CONFIG_DRM_AMDGPU_GART_DEBUGFS
>>> Â Â Â Â Â { "amdgpu_gtt", &amdgpu_ttm_gtt_fops, TTM_PL_TT }, #endif
>>> -Â Â Â { "amdgpu_iova", &amdgpu_ttm_iova_fops, TTM_PL_SYSTEM },
>>> +Â Â Â { "amdgpu_iomem", &amdgpu_ttm_iomem_fops, TTM_PL_SYSTEM },
>>> Â };
>>> Â Â #endif
>>> --
>>> 2.14.1
>>>
>>> _______________________________________________
>>> dri-devel mailing list
>>> dri-devel at lists.freedesktop.org
>>> https://lists.freedesktop.org/mailman/listinfo/dri-devel
>>> _______________________________________________
>>> amd-gfx mailing list
>>> amd-gfx at lists.freedesktop.org
>>> https://lists.freedesktop.org/mailman/listinfo/amd-gfx
>>>
>>
>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-add-support-for-new-iomem-debugfs-entry.patch
Type: text/x-patch
Size: 4293 bytes
Desc: not available
URL: <https://lists.freedesktop.org/archives/amd-gfx/attachments/20180205/5cd396f2/attachment.bin>
