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  1. 04 12月, 2014 1 次提交
  3. 21 11月, 2014 2 次提交
  5. 28 10月, 2014 1 次提交
  7. 03 10月, 2014 1 次提交
  9. 11 9月, 2014 3 次提交
  11. 02 9月, 2014 1 次提交
  13. 28 8月, 2014 2 次提交
  15. 19 8月, 2014 2 次提交
  17. 11 8月, 2014 1 次提交
    • C
      drm/radeon: add userptr support v8 · f72a113a
      由 Christian König 提交于 
      This patch adds an IOCTL for turning a pointer supplied by
userspace into a buffer object.

It imposes several restrictions upon the memory being mapped:

1. It must be page aligned (both start/end addresses, i.e ptr and size).

2. It must be normal system memory, not a pointer into another map of IO
space (e.g. it must not be a GTT mmapping of another object).

3. The BO is mapped into GTT, so the maximum amount of memory mapped at
all times is still the GTT limit.

4. The BO is only mapped readonly for now, so no write support.

5. List of backing pages is only acquired once, so they represent a
snapshot of the first use.

Exporting and sharing as well as mapping of buffer objects created by
this function is forbidden and results in an -EPERM.

v2: squash all previous changes into first public version
v3: fix tabs, map readonly, don't use MM callback any more
v4: set TTM_PAGE_FLAG_SG so that TTM never messes with the pages,
    pin/unpin pages on bind/unbind instead of populate/unpopulate
v5: rebased on 3.17-wip, IOCTL renamed to userptr, reject any unknown
    flags, better handle READONLY flag, improve permission check
v6: fix ptr cast warning, use set_page_dirty/mark_page_accessed on unpin
v7: add warning about it's availability in the API definition
v8: drop access_ok check, fix VM mapping bits
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com> (v4)
Reviewed-by: Jérôme Glisse <jglisse@redhat.com> (v4)
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
      f72a113a
  19. 05 8月, 2014 1 次提交
  21. 22 7月, 2014 2 次提交
  23. 10 6月, 2014 1 次提交
  25. 30 5月, 2014 2 次提交
  27. 04 3月, 2014 1 次提交
  29. 03 3月, 2014 6 次提交
  31. 18 2月, 2014 2 次提交
  33. 30 1月, 2014 1 次提交
  35. 18 12月, 2013 1 次提交
  37. 03 12月, 2013 1 次提交
  39. 16 11月, 2013 1 次提交
  41. 02 11月, 2013 1 次提交
    • M
      drm/radeon: fixup locking inversion between, mmap_sem and reservations · 28a326c5
      由 Maarten Lankhorst 提交于 
      op 08-10-13 18:58, Thomas Hellstrom schreef:
> On 10/08/2013 06:47 PM, Jerome Glisse wrote:
>> On Tue, Oct 08, 2013 at 06:29:35PM +0200, Thomas Hellstrom wrote:
>>> On 10/08/2013 04:55 PM, Jerome Glisse wrote:
>>>> On Tue, Oct 08, 2013 at 04:45:18PM +0200, Christian König wrote:
>>>>> Am 08.10.2013 16:33, schrieb Jerome Glisse:
>>>>>> On Tue, Oct 08, 2013 at 04:14:40PM +0200, Maarten Lankhorst wrote:
>>>>>>> Allocate and copy all kernel memory before doing reservations. This prevents a locking
>>>>>>> inversion between mmap_sem and reservation_class, and allows us to drop the trylocking
>>>>>>> in ttm_bo_vm_fault without upsetting lockdep.
>>>>>>>
>>>>>>> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
>>>>>> I would say NAK. Current code only allocate temporary page in AGP case.
>>>>>> So AGP case is userspace -> temp page -> cs checker -> radeon ib.
>>>>>>
>>>>>> Non AGP is directly memcpy to radeon IB.
>>>>>>
>>>>>> Your patch allocate memory memcpy userspace to it and it will then be
>>>>>> memcpy to IB. Which means you introduce an extra memcpy in the process
>>>>>> not something we want.
>>>>> Totally agree. Additional to that there is no good reason to provide
>>>>> anything else than anonymous system memory to the CS ioctl, so the
>>>>> dependency between the mmap_sem and reservations are not really
>>>>> clear to me.
>>>>>
>>>>> Christian.
>>>> I think is that in other code path you take mmap_sem first then reserve
>>>> bo. But here we reserve bo and then we take mmap_sem because of copy
>>> >from user.
>>>> Cheers,
>>>> Jerome
>>>>
>>> Actually the log message is a little confusing. I think the mmap_sem
>>> locking inversion problem is orthogonal to what's being fixed here.

> >>> This patch fixes the possible recursive bo::reserve caused by
> >>> malicious user-space handing a pointer to ttm memory so that the ttm
> >>> fault handler is called when bos are already reserved. That may
> >>> cause a (possibly interruptible) livelock.

>>> Once that is fixed, we are free to choose the mmap_sem ->
>>> bo::reserve locking order. Currently it's bo::reserve->mmap_sem(),
>>> but the hack required in the ttm fault handler is admittedly a bit
>>> ugly.  The plan is to change the locking order to
>>> mmap_sem->bo::reserve

> >>> I'm not sure if it applies to this particular case, but it should be
> >>> possible to make sure that copy_from_user_inatomic() will always
> >>> succeed, by making sure the pages are present using
> >>> get_user_pages(), and release the pages after
> >>> copy_from_user_inatomic() is done. That way there's no need for a
> >>> double memcpy slowpath, but if the copied data is very fragmented I
> >>> guess the resulting code may look ugly. The get_user_pages()
> >>> function will return an error if it hits TTM pages.

>>> /Thomas
>> get_user_pages + copy_from_user_inatomic is overkill. We should just
>> do get_user_pages which fails with ttm memory and then use copy_highpage
>> helper.
>>
>> Cheers,
>> Jerome
> Yeah, it may well be that that's the preferred solution.
>
> /Thomas
>
I still disagree, and shuffled radeon_ib_get around to be called sooner.

How does the patch below look?
8<-------
Allocate and copy all kernel memory before doing reservations. This prevents a locking
inversion between mmap_sem and reservation_class, and allows us to drop the trylocking
in ttm_bo_vm_fault without upsetting lockdep.

Changes since v1:
- Kill extra memcpy for !AGP case.
Signed-off-by: NMaarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: NJerome Glisse <jglisse@redhat.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
      28a326c5
  43. 19 10月, 2013 1 次提交
  45. 23 9月, 2013 1 次提交
  47. 21 9月, 2013 1 次提交
  49. 16 9月, 2013 1 次提交
  51. 11 9月, 2013 1 次提交
  53. 31 8月, 2013 1 次提交