On 17.02.25 01:01, Alistair Popple wrote:
On Tue, Feb 11, 2025 at 09:33:54AM +0100, David Hildenbrand wrote:
On 11.02.25 06:00, Andrew Morton wrote:
On Mon, 10 Feb 2025 20:37:45 +0100 David Hildenbrand <da...@redhat.com> wrote:
The single "real" user in the tree of make_device_exclusive_range() always
requests making only a single address exclusive. The current implementation
is hard to fix for properly supporting anonymous THP / large folios and
for avoiding messing with rmap walks in weird ways.
So let's always process a single address/page and return folio + page to
minimize page -> folio lookups. This is a preparation for further
changes.
Reject any non-anonymous or hugetlb folios early, directly after GUP.
While at it, extend the documentation of make_device_exclusive() to
clarify some things.
x86_64 allmodconfig:
drivers/gpu/drm/nouveau/nouveau_svm.c: In function 'nouveau_atomic_range_fault':
drivers/gpu/drm/nouveau/nouveau_svm.c:612:68: error: 'folio' undeclared (first
use in this function)
612 | page = make_device_exclusive(mm, start, drm->dev,
&folio);
|
^~~~~
drivers/gpu/drm/nouveau/nouveau_svm.c:612:68: note: each undeclared identifier
is reported only once for each function it appears in
Ah! Because I was carrying on the same branch SVM fixes [1] that are
getting surprisingly little attention so far.
I believe this has been picked up in drm-misc-fixes now:
https://lore.kernel.org/dri-devel/Z69eloo_7LM6NneO@cassiopeiae/
Yes. Both trees should merge without conflicts. However, we can later
get rid of the now-superfluous page_folio() that was required in the drm
fix.
--
Cheers,
David / dhildenb
