lkml.org 
[lkml]   [2022]   [Apr]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 1/3] binder: Use memset_page() in binder_alloc_clear_buf()
    Date
    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_clear_buf() 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() but, instead of open
    coding these two functions and adding a memset() of the virtual address
    of the mapping, prefer memset_page().

    Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
    ---
    drivers/android/binder_alloc.c | 5 +----
    1 file changed, 1 insertion(+), 4 deletions(-)

    diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
    index 2ac1008a5f39..0b3f2f569053 100644
    --- a/drivers/android/binder_alloc.c
    +++ b/drivers/android/binder_alloc.c
    @@ -1175,14 +1175,11 @@ static void binder_alloc_clear_buf(struct binder_alloc *alloc,
    unsigned long size;
    struct page *page;
    pgoff_t pgoff;
    - void *kptr;

    page = binder_alloc_get_page(alloc, buffer,
    buffer_offset, &pgoff);
    size = min_t(size_t, bytes, PAGE_SIZE - pgoff);
    - kptr = kmap(page) + pgoff;
    - memset(kptr, 0, size);
    - kunmap(page);
    + memset_page(page, pgoff, 0, size);
    bytes -= size;
    buffer_offset += size;
    }
    --
    2.34.1
    \
     
     \ /
      Last update: 2022-04-23 12:26    [W:9.009 / U:0.132 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site