Boaz Harrosh wrote: > Currently inherited from sg.c bsg will submit asynchronous request > at the head-of-the-queue, (using "at_head" set in the call to > blk_execute_rq_nowait()). This is bad in situation where the queues > are full but requests need to execute in order. Failing to do that can > cause the first submitted commands to never execute. > > The sg_io_v4->flags member is used and a bit is allocated to denote the > Q_AT_TAIL. Zero is to queue at_head as before, to be compatible with old > code at the write/read path. SG_IO code path behavior was changed so to > be the same as write/read behavior. SG_IO was very rarely used and breaking > compatibility with it is OK at this stage. > > sg_io_hdr at sg.h also has a flags member and uses 3 bits from the first > nibble and one bit from the last nibble. Even though none of these bits > are supported by bsg, The second nibble is allocated for use by bsg. Just > in case. > > Signed-off-by: Boaz Harrosh <bharrosh@xxxxxxxxxxx> > CC: Douglas Gilbert <dgilbert@xxxxxxxxxxxx> > --- > block/bsg.c | 9 +++++++-- > include/linux/bsg.h | 8 ++++++++ > 2 files changed, 15 insertions(+), 2 deletions(-) > Sorrrrrrry bad patch, teach me to never send a patch in the morning before coffee. Will send a version 3 Boaz -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
