From b2460756660c6a6d1be8e35a18521d5c2a3f5823 Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Fri, 19 Feb 2016 09:17:00 +0100 Subject: [PATCH] scsi_dh_alua: Make stpg synchronous The 'activate_complete' function needs to be executed after stpg has finished, so we can as well execute stpg synchronously and call the function directly. Reviewed-by: Bart Van Assche Reviewed-by: Christoph Hellwig Signed-off-by: Hannes Reinecke Signed-off-by: Martin K. Petersen --- drivers/scsi/device_handler/scsi_dh_alua.c | 158 +++++++-------------- 1 file changed, 54 insertions(+), 104 deletions(-) diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 136bc7665b11..467c2cfd09b8 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -169,81 +169,28 @@ done: } /* - * stpg_endio - Evaluate SET TARGET GROUP STATES - * @sdev: the device to be evaluated - * @state: the new target group state - * - * Evaluate a SET TARGET GROUP STATES command response. - */ -static void stpg_endio(struct request *req, int error) -{ - struct alua_dh_data *h = req->end_io_data; - struct scsi_sense_hdr sense_hdr; - unsigned err = SCSI_DH_OK; - - if (host_byte(req->errors) != DID_OK || - msg_byte(req->errors) != COMMAND_COMPLETE) { - err = SCSI_DH_IO; - goto done; - } - - if (scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE, - &sense_hdr)) { - if (sense_hdr.sense_key == NOT_READY && - sense_hdr.asc == 0x04 && sense_hdr.ascq == 0x0a) { - /* ALUA state transition already in progress */ - err = SCSI_DH_OK; - goto done; - } - if (sense_hdr.sense_key == UNIT_ATTENTION) { - err = SCSI_DH_RETRY; - goto done; - } - sdev_printk(KERN_INFO, h->sdev, "%s: stpg failed\n", - ALUA_DH_NAME); - scsi_print_sense_hdr(h->sdev, ALUA_DH_NAME, &sense_hdr); - err = SCSI_DH_IO; - } else if (error) - err = SCSI_DH_IO; - - if (err == SCSI_DH_OK) { - h->state = TPGS_STATE_OPTIMIZED; - sdev_printk(KERN_INFO, h->sdev, - "%s: port group %02x switched to state %c\n", - ALUA_DH_NAME, h->group_id, - print_alua_state(h->state)); - } -done: - req->end_io_data = NULL; - __blk_put_request(req->q, req); - if (h->callback_fn) { - h->callback_fn(h->callback_data, err); - h->callback_fn = h->callback_data = NULL; - } - return; -} - -/* - * submit_stpg - Issue a SET TARGET GROUP STATES command + * submit_stpg - Issue a SET TARGET PORT GROUP command * * Currently we're only setting the current target port group state * to 'active/optimized' and let the array firmware figure out * the states of the remaining groups. */ -static unsigned submit_stpg(struct alua_dh_data *h) +static unsigned submit_stpg(struct scsi_device *sdev, int group_id, + unsigned char *sense) { struct request *rq; + unsigned char stpg_data[8]; int stpg_len = 8; - struct scsi_device *sdev = h->sdev; + int err = 0; /* Prepare the data buffer */ - memset(h->buff, 0, stpg_len); - h->buff[4] = TPGS_STATE_OPTIMIZED & 0x0f; - put_unaligned_be16(h->group_id, &h->buff[6]); + memset(stpg_data, 0, stpg_len); + stpg_data[4] = TPGS_STATE_OPTIMIZED & 0x0f; + put_unaligned_be16(group_id, &stpg_data[6]); - rq = get_alua_req(sdev, h->buff, stpg_len, WRITE); + rq = get_alua_req(sdev, stpg_data, stpg_len, WRITE); if (!rq) - return SCSI_DH_RES_TEMP_UNAVAIL; + return DRIVER_BUSY << 24; /* Prepare the command. */ rq->cmd[0] = MAINTENANCE_OUT; @@ -251,13 +198,17 @@ static unsigned submit_stpg(struct alua_dh_data *h) put_unaligned_be32(stpg_len, &rq->cmd[6]); rq->cmd_len = COMMAND_SIZE(MAINTENANCE_OUT); - rq->sense = h->sense; + rq->sense = sense; memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE); rq->sense_len = 0; - rq->end_io_data = h; - blk_execute_rq_nowait(rq->q, NULL, rq, 1, stpg_endio); - return SCSI_DH_OK; + blk_execute_rq(rq->q, NULL, rq, 1); + if (rq->errors) + err = rq->errors; + + blk_put_request(rq); + + return err; } /* @@ -582,59 +533,59 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ * alua_stpg - Issue a SET TARGET PORT GROUP command * * Issue a SET TARGET PORT GROUP command and evaluate the - * response. Returns SCSI_DH_RETRY if the target port group - * state is found to be in 'transitioning'. - * If SCSI_DH_OK is returned the passed-in 'fn' function - * this function will take care of executing 'fn'. - * Otherwise 'fn' should be executed by the caller with the - * returned error code. + * response. Returns SCSI_DH_RETRY per default to trigger + * a re-evaluation of the target group state or SCSI_DH_OK + * if no further action needs to be taken. */ -static unsigned alua_stpg(struct scsi_device *sdev, struct alua_dh_data *h, - activate_complete fn, void *data) +static unsigned alua_stpg(struct scsi_device *sdev, struct alua_dh_data *h) { - int err = SCSI_DH_OK; - int stpg = 0; - - if (!(h->tpgs & TPGS_MODE_EXPLICIT)) - /* Only implicit ALUA supported */ - goto out; + int retval; + struct scsi_sense_hdr sense_hdr; + if (!(h->tpgs & TPGS_MODE_EXPLICIT)) { + /* Only implicit ALUA supported, retry */ + return SCSI_DH_RETRY; + } switch (h->state) { + case TPGS_STATE_OPTIMIZED: + return SCSI_DH_OK; case TPGS_STATE_NONOPTIMIZED: - stpg = 1; if ((h->flags & ALUA_OPTIMIZE_STPG) && !h->pref && (h->tpgs & TPGS_MODE_IMPLICIT)) - stpg = 0; + return SCSI_DH_OK; break; case TPGS_STATE_STANDBY: case TPGS_STATE_UNAVAILABLE: - stpg = 1; break; case TPGS_STATE_OFFLINE: - err = SCSI_DH_IO; - break; + return SCSI_DH_IO; case TPGS_STATE_TRANSITIONING: - err = SCSI_DH_RETRY; break; default: - break; + sdev_printk(KERN_INFO, sdev, + "%s: stpg failed, unhandled TPGS state %d", + ALUA_DH_NAME, h->state); + return SCSI_DH_NOSYS; } + retval = submit_stpg(sdev, h->group_id, h->sense); - if (stpg) { - h->callback_fn = fn; - h->callback_data = data; - err = submit_stpg(h); - if (err != SCSI_DH_OK) - h->callback_fn = h->callback_data = NULL; - else - fn = NULL; + if (retval) { + if (!scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE, + &sense_hdr)) { + sdev_printk(KERN_INFO, sdev, + "%s: stpg failed, result %d", + ALUA_DH_NAME, retval); + if (driver_byte(retval) == DRIVER_BUSY) + return SCSI_DH_DEV_TEMP_BUSY; + } else { + sdev_printk(KERN_INFO, h->sdev, "%s: stpg failed\n", + ALUA_DH_NAME); + scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr); + } } -out: - if (fn) - fn(data, err); - - return err; + /* Retry RTPG */ + return SCSI_DH_RETRY; } /* @@ -722,10 +673,9 @@ static int alua_activate(struct scsi_device *sdev, if (optimize_stpg) h->flags |= ALUA_OPTIMIZE_STPG; - err = alua_stpg(sdev, h, fn, data); - + err = alua_stpg(sdev, h); out: - if (err != SCSI_DH_OK && fn) + if (fn) fn(data, err); return 0; } -- 2.20.1