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| author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2020-11-27 19:41:19 +0300 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2021-01-12 16:15:17 +0300 |
| commit | 04769cb1c45a919cd94b931e6494d2a9afc32914 (patch) | |
| tree | 6866e55a7a05329ede8acf045c3fdcf6897a276a /drivers/media/common | |
| parent | d88a0c169bd535182547c54933a38b2afd553f44 (diff) | |
| download | linux-04769cb1c45a919cd94b931e6494d2a9afc32914.tar.xz | |
mm/frame-vector: Use FOLL_LONGTERM
This is used by media/videbuf2 for persistent dma mappings, not just
for a single dma operation and then freed again, so needs
FOLL_LONGTERM.
Unfortunately current pup_locked doesn't support FOLL_LONGTERM due to
locking issues. Rework the code to pull the pup path out from the
mmap_sem critical section as suggested by Jason.
By relying entirely on the vma checks in pin_user_pages and follow_pfn
(for vm_flags and vma_is_fsdax) we can also streamline the code a lot.
Note that pin_user_pages_fast is a safe replacement despite the
seeming lack of checking for vma->vm_flasg & (VM_IO | VM_PFNMAP). Such
ptes are marked with pte_mkspecial (which pup_fast rejects in the
fastpath), and only architectures supporting that support the
pin_user_pages_fast fastpath.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Pawel Osciak <pawel@osciak.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Tomasz Figa <tfiga@chromium.org>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: linux-mm@kvack.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-media@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20201127164131.2244124-6-daniel.vetter@ffwll.ch
Diffstat (limited to 'drivers/media/common')
| -rw-r--r-- | drivers/media/common/videobuf2/videobuf2-memops.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/drivers/media/common/videobuf2/videobuf2-memops.c b/drivers/media/common/videobuf2/videobuf2-memops.c index 6e9e05153f4e..9dd6c27162f4 100644 --- a/drivers/media/common/videobuf2/videobuf2-memops.c +++ b/drivers/media/common/videobuf2/videobuf2-memops.c @@ -40,7 +40,6 @@ struct frame_vector *vb2_create_framevec(unsigned long start, unsigned long first, last; unsigned long nr; struct frame_vector *vec; - unsigned int flags = FOLL_FORCE | FOLL_WRITE; first = start >> PAGE_SHIFT; last = (start + length - 1) >> PAGE_SHIFT; @@ -48,7 +47,7 @@ struct frame_vector *vb2_create_framevec(unsigned long start, vec = frame_vector_create(nr); if (!vec) return ERR_PTR(-ENOMEM); - ret = get_vaddr_frames(start & PAGE_MASK, nr, flags, vec); + ret = get_vaddr_frames(start & PAGE_MASK, nr, vec); if (ret < 0) goto out_destroy; /* We accept only complete set of PFNs */ |