> 2023年5月12日 10:07，Chaitanya Kulkarni <kch@xxxxxxxxxx> 写道： > > Flush requests are implemented as REQ_OP_WRITE + REQ_OP_PREFLUSH > combination and not REQ_OP_FLUSH + REQ_PREFLUSH combination. > > This unclear nature has lead to the confusion and bugs in the code for > block drivers causing more work for testing, reviews and fixes :- > > 1. https://lore.kernel.org/all/ZFHgefWofVt24tRl@xxxxxxxxxxxxx/ > 2. https://marc.info/?l=linux-block&m=168386364026498&w=2 > > Add a macro (name can me more meaningful) with a meaningful comment > clearing the confusion and replace the REQ_OP_WRITE | REQ_PREFLUSH with > the new macro name that also saves code repetation. > > Signed-off-by: Chaitanya Kulkarni <kch@xxxxxxxxxx> > --- a/include/linux/blk_types.h > +++ b/include/linux/blk_types.h > @@ -455,6 +455,13 @@ enum req_flag_bits { > #define REQ_NOMERGE_FLAGS \ > (REQ_NOMERGE | REQ_PREFLUSH | REQ_FUA) > > +/* > + * Flush requests are implemented as REQ_OP_WRITE + REQ_OP_PREFLUSH combination > + * and not REQ_OP_FLUSH + REQ_PREFLUSH combination. > + */ > + > +#define REQ_FLUSH_OPF (REQ_OP_WRITE | REQ_PREFLUSH) > + > enum stat_group { > STAT_READ, > STAT_WRITE, > -- Personally I like current explicit way, it is simpler than an extra macro. This is just my own points, FYI. Thanks. Coly Li
