diff options
| author | Hans Verkuil <hverkuil-cisco@xs4all.nl> | 2022-11-28 08:23:56 +0000 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@kernel.org> | 2022-12-06 07:14:31 +0000 |
| commit | e2fc6edd37ba487c64f4dd09f7118b3e45b12d88 (patch) | |
| tree | 26266931ca718aa0229833e39b3132bb00607c38 /drivers/media/common/videobuf2/videobuf2-memops.c | |
| parent | 1aba7930c63ea57b4918dc61dcc315f451cec21e (diff) | |
media: videobuf2: revert "get_userptr: buffers are always writable"
Commit 707947247e95 ("media: videobuf2-vmalloc: get_userptr: buffers are
always writable") caused problems in a corner case (passing read-only
shmem memory as a userptr). So revert this patch.
The original problem for which that commit was originally made is
something that I could not reproduce after reverting it. So just go
back to the way it was for many years, and if problems arise in
the future, then another approach should be taken to resolve it.
This patch is based on a patch from Hirokazu.
Fixes: 707947247e95 ("media: videobuf2-vmalloc: get_userptr: buffers are always writable")
Signed-off-by: Hirokazu Honda <hiroh@chromium.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Acked-by: Tomasz Figa <tfiga@chromium.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Diffstat (limited to 'drivers/media/common/videobuf2/videobuf2-memops.c')
| -rw-r--r-- | drivers/media/common/videobuf2/videobuf2-memops.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/media/common/videobuf2/videobuf2-memops.c b/drivers/media/common/videobuf2/videobuf2-memops.c index 9dd6c27162f4..f9a4ec44422e 100644 --- a/drivers/media/common/videobuf2/videobuf2-memops.c +++ b/drivers/media/common/videobuf2/videobuf2-memops.c @@ -26,6 +26,7 @@ * vb2_create_framevec() - map virtual addresses to pfns * @start: Virtual user address where we start mapping * @length: Length of a range to map + * @write: Should we map for writing into the area * * This function allocates and fills in a vector with pfns corresponding to * virtual address range passed in arguments. If pfns have corresponding pages, @@ -34,7 +35,8 @@ * failure. Returned vector needs to be freed via vb2_destroy_pfnvec(). */ struct frame_vector *vb2_create_framevec(unsigned long start, - unsigned long length) + unsigned long length, + bool write) { int ret; unsigned long first, last; @@ -47,7 +49,7 @@ 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, vec); + ret = get_vaddr_frames(start & PAGE_MASK, nr, write, vec); if (ret < 0) goto out_destroy; /* We accept only complete set of PFNs */ |