diff options
| author | Fabio M. De Francesco <fmdefrancesco@gmail.com> | 2022-04-25 19:57:53 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-04-26 12:51:31 +0200 |
| commit | 1d625960e41907af706f573a3cd097595a0ade63 (patch) | |
| tree | 8e5a08d2d6f7ff7e3def7d8be254b6f581075aae /drivers/android/binder_alloc.c | |
| parent | 26eff2d66aff33527c7872277ab9c9d8478a978c (diff) | |
| download | lwn-1d625960e41907af706f573a3cd097595a0ade63.tar.gz lwn-1d625960e41907af706f573a3cd097595a0ade63.zip | |
binder: Use kmap_local_page() in binder_alloc_copy_user_to_buffer()
The use of kmap() is being deprecated in favor of kmap_local_page()
where it is feasible. With kmap_local_page(), the mapping is per
thread, CPU local and not globally visible.
binder_alloc_copy_user_to_buffer() is a function where the use of
kmap_local_page() in place of kmap() is correctly suited because
the mapping is local to the thread.
Therefore, use kmap_local_page() / kunmap_local().
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Link: https://lore.kernel.org/r/20220425175754.8180-3-fmdefrancesco@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/android/binder_alloc.c')
| -rw-r--r-- | drivers/android/binder_alloc.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c index 0b3f2f569053..0875c463c002 100644 --- a/drivers/android/binder_alloc.c +++ b/drivers/android/binder_alloc.c @@ -1217,9 +1217,9 @@ binder_alloc_copy_user_to_buffer(struct binder_alloc *alloc, page = binder_alloc_get_page(alloc, buffer, buffer_offset, &pgoff); size = min_t(size_t, bytes, PAGE_SIZE - pgoff); - kptr = kmap(page) + pgoff; + kptr = kmap_local_page(page) + pgoff; ret = copy_from_user(kptr, from, size); - kunmap(page); + kunmap_local(kptr); if (ret) return bytes - size + ret; bytes -= size; |