diff options
Diffstat (limited to 'drivers/scsi/scsi_lib.c')
-rw-r--r-- | drivers/scsi/scsi_lib.c | 47 |
1 files changed, 44 insertions, 3 deletions
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 621d841d819a..35e381f6d371 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -241,7 +241,7 @@ int __scsi_execute(struct scsi_device *sdev, const unsigned char *cmd, /* * head injection *required* here otherwise quiesce won't work */ - blk_execute_rq(NULL, req, 1); + blk_execute_rq(req, true); /* * Some devices (USB mass-storage in particular) may transfer @@ -543,8 +543,9 @@ static bool scsi_end_request(struct request *req, blk_status_t error, if (blk_update_request(req, error, bytes)) return true; + // XXX: if (blk_queue_add_random(q)) - add_disk_randomness(req->rq_disk); + add_disk_randomness(req->q->disk); if (!blk_rq_is_passthrough(req)) { WARN_ON_ONCE(!(cmd->flags & SCMD_INITIALIZED)); @@ -617,6 +618,46 @@ 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 +835,7 @@ 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: |