buffmem_desc 627 include/linux/soundcard.h #define SNDCTL_DSP_MAPINBUF _SIOR ('P', 19, buffmem_desc) buffmem_desc 628 include/linux/soundcard.h #define SNDCTL_DSP_MAPOUTBUF _SIOR ('P', 20, buffmem_desc) buffmem_desc 2584 sound/core/oss/pcm_oss.c (struct buffmem_desc __user *) arg);