• Tejun Heo's avatar
    sysfs: use transient write buffer · 8ef445f0
    Tejun Heo authored
    
    
    There isn't much to be gained by keeping around kernel buffer while a
    file is open especially as the read path planned to be converted to
    use seq_file and won't use the buffer.  This patch makes
    sysfs_write_file() use per-write transient buffer instead of
    sysfs_open_file->page.
    
    This simplifies the write path, enables removing sysfs_open_file->page
    once read path is updated and will help merging bin file write path
    which already requires the use of a transient buffer due to a locking
    order issue.
    
    As the function comments of flush_write_buffer() and
    sysfs_write_buffer() are being updated anyway, reformat them so that
    they're more conventional.
    
    v2: Use min_t() instead of min() in sysfs_write_file() to avoid build
        warning on arm.  Reported by build test robot.
    Signed-off-by: default avatarTejun Heo <tj@kernel.org>
    Cc: kbuild test robot <fengguang.wu@intel.com>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    8ef445f0