Use the helper comedi_buf_write_n_allocated() to clarify the check to make sure the number of bytes to free is not more than the number of bytes allocated.
Signed-off-by: H Hartley Sweeten <[email protected]> Cc: Ian Abbott <[email protected]> Cc: Greg Kroah-Hartman <[email protected]> --- drivers/staging/comedi/comedi_buf.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/staging/comedi/comedi_buf.c b/drivers/staging/comedi/comedi_buf.c index c4ec083..827295f 100644 --- a/drivers/staging/comedi/comedi_buf.c +++ b/drivers/staging/comedi/comedi_buf.c @@ -254,11 +254,12 @@ static unsigned int comedi_buf_munge(struct comedi_async *async, /* transfers a chunk from writer to filled buffer space */ unsigned comedi_buf_write_free(struct comedi_async *async, unsigned int nbytes) { - if ((int)(async->buf_write_count + nbytes - - async->buf_write_alloc_count) > 0) { + unsigned int allocated = comedi_buf_write_n_allocated(async); + + if (nbytes > allocated) { dev_info(async->subdevice->device->class_dev, "attempted to write-free more bytes than have been write-allocated.\n"); - nbytes = async->buf_write_alloc_count - async->buf_write_count; + nbytes = allocated; } async->buf_write_count += nbytes; async->buf_write_ptr += nbytes; -- 1.8.0 _______________________________________________ devel mailing list [email protected] http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
