On Mon, Nov 11, 2013 at 6:47 PM, Huang Shijie <b32955@xxxxxxxxxxxxx> wrote: > 于 2013年11月12日 02:23, Brian Norris 写道: >> (2) The second switched the whole NAND buffer over to a kzalloc'd >> buffer, with NAND_OWN_BUFFERS. I'm not a huge fan of >> NAND_OWN_BUFFERS, and I think drivers should only be using it if >> they really need it, for special buffer placement or some other good >> reason. You just happen to need a buffer "too early", where you can >> really just allocate a small temporary buffer. > why I use the NAND_OWN_BUFFERS? just for a small temporary buffer? > the answer is no. > > For imx23, the work flow is like this: > [1] first check the fingerprint, if we can find it, we will return > immediately. > [2] if [1] failed, such as you erase all the partitions, the gpmi will call > mx23_write_transcription_stamp() to write the fingerprint. > > So the @chip->buffer is not only used by the > mx23_check_transcription_stamp(), > but _also_ used by the mx23_write_transcription_stamp() when the gpmi > can not find any > fingerprint in the NAND page. Right, thanks for pointing this out. > That's why i use the NAND_OWN_BUFFERS, the buffer can be used by both > the mx23_check_transcription_stamp() > and mx23_write_transcription_stamp(). I will resume discussion on your NAND_OWN_BUFFERS patch. Brian -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html