From 79478bf9ea9fa48d30836afa796ac13d8a0f320b Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 17 Nov 2021 07:13:54 +0100 Subject: block: move blk_rq_err_bytes to scsi blk_rq_err_bytes is only used by the scsi midlayer, so move it there. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Link: https://lore.kernel.org/r/20211117061404.331732-2-hch@lst.de Signed-off-by: Jens Axboe --- drivers/scsi/scsi_lib.c | 42 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 41 insertions(+), 1 deletion(-) (limited to 'drivers/scsi/scsi_lib.c') diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 621d841d819a..5e8b5ecb3245 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -617,6 +617,46 @@ static blk_status_t scsi_result_to_blk_status(struct scsi_cmnd *cmd, int result) } } +/** + * scsi_rq_err_bytes - determine number of bytes till the next failure boundary + * @rq: request to examine + * + * Description: + * A request could be merge of IOs which require different failure + * handling. This function determines the number of bytes which + * can be failed from the beginning of the request without + * crossing into area which need to be retried further. + * + * Return: + * The number of bytes to fail. + */ +static unsigned int scsi_rq_err_bytes(const struct request *rq) +{ + unsigned int ff = rq->cmd_flags & REQ_FAILFAST_MASK; + unsigned int bytes = 0; + struct bio *bio; + + if (!(rq->rq_flags & RQF_MIXED_MERGE)) + return blk_rq_bytes(rq); + + /* + * Currently the only 'mixing' which can happen is between + * different fastfail types. We can safely fail portions + * which have all the failfast bits that the first one has - + * the ones which are at least as eager to fail as the first + * one. + */ + for (bio = rq->bio; bio; bio = bio->bi_next) { + if ((bio->bi_opf & ff) != ff) + break; + bytes += bio->bi_iter.bi_size; + } + + /* this could lead to infinite loop */ + BUG_ON(blk_rq_bytes(rq) && !bytes); + return bytes; +} + /* Helper for scsi_io_completion() when "reprep" action required. */ static void scsi_io_completion_reprep(struct scsi_cmnd *cmd, struct request_queue *q) @@ -794,7 +834,7 @@ static void scsi_io_completion_action(struct scsi_cmnd *cmd, int result) scsi_print_command(cmd); } } - if (!scsi_end_request(req, blk_stat, blk_rq_err_bytes(req))) + if (!scsi_end_request(req, blk_stat, scsi_rq_err_bytes(req))) return; fallthrough; case ACTION_REPREP: -- cgit v1.2.3