diff options
Diffstat (limited to 'drivers/scsi/scsi_lib.c')
| -rw-r--r-- | drivers/scsi/scsi_lib.c | 65 |
1 files changed, 34 insertions, 31 deletions
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 17a617db9ae0..ef08029a0079 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -75,13 +75,6 @@ int scsi_init_sense_cache(struct Scsi_Host *shost) return ret; } -/* - * When to reinvoke queueing after a resource shortage. It's 3 msecs to - * not change behaviour from the previous unplug mechanism, experimentation - * may prove this needs changing. - */ -#define SCSI_QUEUE_DELAY 3 - static void scsi_set_blocked(struct scsi_cmnd *cmd, int reason) { @@ -118,7 +111,7 @@ scsi_set_blocked(struct scsi_cmnd *cmd, int reason) } } -static void scsi_mq_requeue_cmd(struct scsi_cmnd *cmd) +static void scsi_mq_requeue_cmd(struct scsi_cmnd *cmd, unsigned long msecs) { struct request *rq = scsi_cmd_to_rq(cmd); @@ -128,7 +121,12 @@ static void scsi_mq_requeue_cmd(struct scsi_cmnd *cmd) } else { WARN_ON_ONCE(true); } - blk_mq_requeue_request(rq, true); + + if (msecs) { + blk_mq_requeue_request(rq, false); + blk_mq_delay_kick_requeue_list(rq->q, msecs); + } else + blk_mq_requeue_request(rq, true); } /** @@ -658,14 +656,6 @@ static unsigned int scsi_rq_err_bytes(const struct request *rq) 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) -{ - /* A new command will be prepared and issued. */ - scsi_mq_requeue_cmd(cmd); -} - static bool scsi_cmd_runtime_exceeced(struct scsi_cmnd *cmd) { struct request *req = scsi_cmd_to_rq(cmd); @@ -683,14 +673,21 @@ static bool scsi_cmd_runtime_exceeced(struct scsi_cmnd *cmd) return false; } +/* + * When ALUA transition state is returned, reprep the cmd to + * use the ALUA handler's transition timeout. Delay the reprep + * 1 sec to avoid aggressive retries of the target in that + * state. + */ +#define ALUA_TRANSITION_REPREP_DELAY 1000 + /* Helper for scsi_io_completion() when special action required. */ static void scsi_io_completion_action(struct scsi_cmnd *cmd, int result) { - struct request_queue *q = cmd->device->request_queue; struct request *req = scsi_cmd_to_rq(cmd); int level = 0; - enum {ACTION_FAIL, ACTION_REPREP, ACTION_RETRY, - ACTION_DELAYED_RETRY} action; + enum {ACTION_FAIL, ACTION_REPREP, ACTION_DELAYED_REPREP, + ACTION_RETRY, ACTION_DELAYED_RETRY} action; struct scsi_sense_hdr sshdr; bool sense_valid; bool sense_current = true; /* false implies "deferred sense" */ @@ -779,8 +776,8 @@ static void scsi_io_completion_action(struct scsi_cmnd *cmd, int result) action = ACTION_DELAYED_RETRY; break; case 0x0a: /* ALUA state transition */ - blk_stat = BLK_STS_TRANSPORT; - fallthrough; + action = ACTION_DELAYED_REPREP; + break; default: action = ACTION_FAIL; break; @@ -839,7 +836,10 @@ static void scsi_io_completion_action(struct scsi_cmnd *cmd, int result) return; fallthrough; case ACTION_REPREP: - scsi_io_completion_reprep(cmd, q); + scsi_mq_requeue_cmd(cmd, 0); + break; + case ACTION_DELAYED_REPREP: + scsi_mq_requeue_cmd(cmd, ALUA_TRANSITION_REPREP_DELAY); break; case ACTION_RETRY: /* Retry the same command immediately */ @@ -933,7 +933,7 @@ static int scsi_io_completion_nz_result(struct scsi_cmnd *cmd, int result, * command block will be released and the queue function will be goosed. If we * are not done then we have to figure out what to do next: * - * a) We can call scsi_io_completion_reprep(). The request will be + * a) We can call scsi_mq_requeue_cmd(). The request will be * unprepared and put back on the queue. Then a new command will * be created for it. This should be used if we made forward * progress, or if we want to switch from READ(10) to READ(6) for @@ -949,7 +949,6 @@ static int scsi_io_completion_nz_result(struct scsi_cmnd *cmd, int result, void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes) { int result = cmd->result; - struct request_queue *q = cmd->device->request_queue; struct request *req = scsi_cmd_to_rq(cmd); blk_status_t blk_stat = BLK_STS_OK; @@ -986,7 +985,7 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes) * request just queue the command up again. */ if (likely(result == 0)) - scsi_io_completion_reprep(cmd, q); + scsi_mq_requeue_cmd(cmd, 0); else scsi_io_completion_action(cmd, result); } @@ -1549,7 +1548,6 @@ static blk_status_t scsi_prepare_cmd(struct request *req) scsi_init_command(sdev, cmd); cmd->eh_eflags = 0; - cmd->allowed = 0; cmd->prot_type = 0; cmd->prot_flags = 0; cmd->submitter = 0; @@ -1600,6 +1598,8 @@ static blk_status_t scsi_prepare_cmd(struct request *req) return ret; } + /* Usually overridden by the ULP */ + cmd->allowed = 0; memset(cmd->cmnd, 0, sizeof(cmd->cmnd)); return scsi_cmd_to_driver(cmd)->init_command(cmd); } @@ -1648,6 +1648,13 @@ static void scsi_mq_put_budget(struct request_queue *q, int budget_token) sbitmap_put(&sdev->budget_map, budget_token); } +/* + * When to reinvoke queueing after a resource shortage. It's 3 msecs to + * not change behaviour from the previous unplug mechanism, experimentation + * may prove this needs changing. + */ +#define SCSI_QUEUE_DELAY 3 + static int scsi_mq_get_budget(struct request_queue *q) { struct scsi_device *sdev = q->queuedata; @@ -1876,10 +1883,6 @@ void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q) blk_queue_max_integrity_segments(q, shost->sg_prot_tablesize); } - if (dev->dma_mask) { - shost->max_sectors = min_t(unsigned int, shost->max_sectors, - dma_max_mapping_size(dev) >> SECTOR_SHIFT); - } blk_queue_max_hw_sectors(q, shost->max_sectors); blk_queue_segment_boundary(q, shost->dma_boundary); dma_set_seg_boundary(dev, shost->dma_boundary); |