mirror_ubuntu-kernels/include
Chris Wilson b65a948973 drm/i915/userptr: Probe existence of backing struct pages upon creation
Jason Ekstrand requested a more efficient method than userptr+set-domain
to determine if the userptr object was backed by a complete set of pages
upon creation. To be more efficient than simply populating the userptr
using get_user_pages() (as done by the call to set-domain or execbuf),
we can walk the tree of vm_area_struct and check for gaps or vma not
backed by struct page (VM_PFNMAP). The question is how to handle
VM_MIXEDMAP which may be either struct page or pfn backed...

With discrete we are going to drop support for set_domain(), so offering
a way to probe the pages, without having to resort to dummy batches has
been requested.

v2:
- add new query param for the PROBE flag, so userspace can easily
  check if the kernel supports it(Jason).
- use mmap_read_{lock, unlock}.
- add some kernel-doc.
v3:
- In the docs also mention that PROBE doesn't guarantee that the pages
  will remain valid by the time they are actually used(Tvrtko).
- Add a small comment for the hole finding logic(Jason).
- Move the param next to all the other params which just return true.

Testcase: igt/gem_userptr_blits/probe
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Kenneth Graunke <kenneth@whitecape.org>
Cc: Jason Ekstrand <jason@jlekstrand.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Ramalingam C <ramalingam.c@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Acked-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Acked-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210723113405.427004-1-matthew.auld@intel.com
2021-08-05 11:34:00 +02:00
..
acpi IOMMU Updates for Linux v5.14 2021-07-02 13:22:47 -07:00
asm-generic This pull request contains the following changes for UML: 2021-07-09 10:19:13 -07:00
clocksource
crypto
drm Merge drm/drm-next into drm-intel-gt-next 2021-07-13 15:52:51 -04:00
dt-bindings ARM: Drivers for 5.14 2021-07-10 09:46:20 -07:00
keys
kunit linux-kselftest-kunit-fixes-5.14-rc1 2021-07-02 12:58:26 -07:00
kvm
linux Kbuild updates for v5.14 2021-07-10 11:01:38 -07:00
math-emu
media
memory
misc
net Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-07-03 11:30:04 -07:00
pcmcia
ras
rdma
scsi SCSI misc on 20210702 2021-07-02 15:14:36 -07:00
soc ARM: Drivers for 5.14 2021-07-10 09:46:20 -07:00
sound ASoC: Updates for v5.14 2021-07-01 08:36:12 +02:00
target
trace Merge branch 'core-rcu-2021.07.04' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu 2021-07-04 12:58:33 -07:00
uapi drm/i915/userptr: Probe existence of backing struct pages upon creation 2021-08-05 11:34:00 +02:00
vdso
video
xen xen: sync include/xen/interface/io/ring.h with Xen's newest version 2021-07-05 09:49:45 +02:00