| Message ID | 1440679281-13234-12-git-send-email-hare@suse.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, Aug 27, 2015 at 02:41:09PM +0200, Hannes Reinecke wrote: > We should be issuing STPG synchronously as we need to > evaluate the return code on failure. This looks right, but I think the patch needs to be split and needs a way better changelog. patch 1: - factor out the alua_stpg helper patch 2: - async STPG - please explain that alua_activate will now block and why this is ok patch 3: - add the new call to alua_rtpg and why it's added -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 09/01/2015 12:04 PM, Christoph Hellwig wrote: > On Thu, Aug 27, 2015 at 02:41:09PM +0200, Hannes Reinecke wrote: >> We should be issuing STPG synchronously as we need to >> evaluate the return code on failure. > > This looks right, but I think the patch needs to be split and needs > a way better changelog. > > patch 1: > - factor out the alua_stpg helper > > patch 2: > - async STPG > - please explain that alua_activate will now block and why this is ok > > patch 3: > - add the new call to alua_rtpg and why it's added > Okay, will be doing so with the next round. Cheers, Hannes
On Thu, 2015-08-27 at 14:41 +0200, Hannes Reinecke wrote: > We should be issuing STPG synchronously as we need to > evaluate the return code on failure. > > Signed-off-by: Hannes Reinecke <hare@suse.de> > --- > drivers/scsi/device_handler/scsi_dh_alua.c | 179 +++++++++++++---------------- > 1 file changed, 83 insertions(+), 96 deletions(-) > > diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c > index 9e2b3af..fd0385e 100644 > --- a/drivers/scsi/device_handler/scsi_dh_alua.c > +++ b/drivers/scsi/device_handler/scsi_dh_alua.c > @@ -172,76 +172,28 @@ 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)) { > - err = alua_check_sense(h->sdev, &sense_hdr); > - if (err == ADD_TO_MLQUEUE) { > - 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 > * > * 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; > @@ -249,13 +201,17 @@ 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 = h->senselen = 0; > - rq->end_io_data = h; > + rq->sense_len = 0; > + > + blk_execute_rq(rq->q, NULL, rq, 1); > + if (rq->errors) > + err = rq->errors; > + > + blk_put_request(rq); > > - blk_execute_rq_nowait(rq->q, NULL, rq, 1, stpg_endio); > - return SCSI_DH_OK; > + return err; > } > > /* > @@ -619,6 +575,68 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ > } > > /* > + * alua_stpg - Issue a SET TARGET GROUP STATES command > + * > + * Issue a SET TARGET GROUP STATES command and evaluate the > + * response. Returns SCSI_DH_RETRY per default to trigger > + * a re-evaluation of the target group state. > + */ > +static unsigned alua_stpg(struct scsi_device *sdev, struct alua_dh_data *h) > +{ > + 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: > + if ((h->flags & ALUA_OPTIMIZE_STPG) && > + !h->pref && > + (h->tpgs & TPGS_MODE_IMPLICIT)) > + return SCSI_DH_OK; > + break; > + case TPGS_STATE_STANDBY: > + case TPGS_STATE_UNAVAILABLE: > + break; > + case TPGS_STATE_OFFLINE: > + return SCSI_DH_IO; > + break; > + case TPGS_STATE_TRANSITIONING: > + break; > + default: > + sdev_printk(KERN_INFO, sdev, > + "%s: stpg failed, unhandled TPGS state %d", > + ALUA_DH_NAME, h->state); > + return SCSI_DH_NOSYS; > + break; > + } > + /* Set state to transitioning */ > + h->state = TPGS_STATE_TRANSITIONING; > + retval = submit_stpg(sdev, h->group_id, h->sense); > + > + 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); > + } > + } > + /* Retry RTPG */ > + return SCSI_DH_RETRY; > +} > + > +/* > * alua_initialize - Initialize ALUA state > * @sdev: the device to be initialized > * > @@ -695,7 +713,6 @@ static int alua_activate(struct scsi_device *sdev, > { > struct alua_dh_data *h = sdev->handler_data; > int err = SCSI_DH_OK; > - int stpg = 0; > > err = alua_rtpg(sdev, h, 1); > if (err != SCSI_DH_OK) > @@ -704,39 +721,9 @@ static int alua_activate(struct scsi_device *sdev, > if (optimize_stpg) > h->flags |= ALUA_OPTIMIZE_STPG; > > - if (h->tpgs & TPGS_MODE_EXPLICIT) { > - switch (h->state) { > - case TPGS_STATE_NONOPTIMIZED: > - stpg = 1; > - if ((h->flags & ALUA_OPTIMIZE_STPG) && > - (!h->pref) && > - (h->tpgs & TPGS_MODE_IMPLICIT)) > - stpg = 0; > - break; > - case TPGS_STATE_STANDBY: > - case TPGS_STATE_UNAVAILABLE: > - stpg = 1; > - break; > - case TPGS_STATE_OFFLINE: > - err = SCSI_DH_IO; > - break; > - case TPGS_STATE_TRANSITIONING: > - err = SCSI_DH_RETRY; > - break; > - default: > - break; > - } > - } > - > - if (stpg) { > - h->callback_fn = fn; > - h->callback_data = data; > - err = submit_stpg(h); > - if (err == SCSI_DH_OK) > - return 0; > - h->callback_fn = h->callback_data = NULL; > - } > - > + err = alua_stpg(sdev, h); > + if (err == SCSI_DH_RETRY) > + err = alua_rtpg(sdev, h, 1); > out: > if (fn) > fn(data, err); submit_stpg() now returns DRIVER_BUSY << 24 instead of SCSI_DH_RES_TEMP_UNAVAIL, so you are changing the return code semantics here as in patch 5/23. That's fine, but probably should be mentioned in the patch description. The removed stpg_endio() code *did* evaluate the SCSI error code, and the code that has replaced it doesn't exactly do the same thing, so what difference in behavior are we going to get here? Reviewed-by: Ewan D. Milne <emilne@redhat.com> -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 09/22/2015 08:50 PM, Ewan Milne wrote: > On Thu, 2015-08-27 at 14:41 +0200, Hannes Reinecke wrote: >> We should be issuing STPG synchronously as we need to >> evaluate the return code on failure. >> >> Signed-off-by: Hannes Reinecke <hare@suse.de> >> --- >> drivers/scsi/device_handler/scsi_dh_alua.c | 179 +++++++++++++---------------- >> 1 file changed, 83 insertions(+), 96 deletions(-) >> >> diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c >> index 9e2b3af..fd0385e 100644 >> --- a/drivers/scsi/device_handler/scsi_dh_alua.c >> +++ b/drivers/scsi/device_handler/scsi_dh_alua.c >> @@ -172,76 +172,28 @@ 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)) { >> - err = alua_check_sense(h->sdev, &sense_hdr); >> - if (err == ADD_TO_MLQUEUE) { >> - 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 >> * >> * 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; >> @@ -249,13 +201,17 @@ 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 = h->senselen = 0; >> - rq->end_io_data = h; >> + rq->sense_len = 0; >> + >> + blk_execute_rq(rq->q, NULL, rq, 1); >> + if (rq->errors) >> + err = rq->errors; >> + >> + blk_put_request(rq); >> >> - blk_execute_rq_nowait(rq->q, NULL, rq, 1, stpg_endio); >> - return SCSI_DH_OK; >> + return err; >> } >> >> /* >> @@ -619,6 +575,68 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ >> } >> >> /* >> + * alua_stpg - Issue a SET TARGET GROUP STATES command >> + * >> + * Issue a SET TARGET GROUP STATES command and evaluate the >> + * response. Returns SCSI_DH_RETRY per default to trigger >> + * a re-evaluation of the target group state. >> + */ >> +static unsigned alua_stpg(struct scsi_device *sdev, struct alua_dh_data *h) >> +{ >> + 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: >> + if ((h->flags & ALUA_OPTIMIZE_STPG) && >> + !h->pref && >> + (h->tpgs & TPGS_MODE_IMPLICIT)) >> + return SCSI_DH_OK; >> + break; >> + case TPGS_STATE_STANDBY: >> + case TPGS_STATE_UNAVAILABLE: >> + break; >> + case TPGS_STATE_OFFLINE: >> + return SCSI_DH_IO; >> + break; >> + case TPGS_STATE_TRANSITIONING: >> + break; >> + default: >> + sdev_printk(KERN_INFO, sdev, >> + "%s: stpg failed, unhandled TPGS state %d", >> + ALUA_DH_NAME, h->state); >> + return SCSI_DH_NOSYS; >> + break; >> + } >> + /* Set state to transitioning */ >> + h->state = TPGS_STATE_TRANSITIONING; >> + retval = submit_stpg(sdev, h->group_id, h->sense); >> + >> + 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); >> + } >> + } >> + /* Retry RTPG */ >> + return SCSI_DH_RETRY; >> +} >> + >> +/* >> * alua_initialize - Initialize ALUA state >> * @sdev: the device to be initialized >> * >> @@ -695,7 +713,6 @@ static int alua_activate(struct scsi_device *sdev, >> { >> struct alua_dh_data *h = sdev->handler_data; >> int err = SCSI_DH_OK; >> - int stpg = 0; >> >> err = alua_rtpg(sdev, h, 1); >> if (err != SCSI_DH_OK) >> @@ -704,39 +721,9 @@ static int alua_activate(struct scsi_device *sdev, >> if (optimize_stpg) >> h->flags |= ALUA_OPTIMIZE_STPG; >> >> - if (h->tpgs & TPGS_MODE_EXPLICIT) { >> - switch (h->state) { >> - case TPGS_STATE_NONOPTIMIZED: >> - stpg = 1; >> - if ((h->flags & ALUA_OPTIMIZE_STPG) && >> - (!h->pref) && >> - (h->tpgs & TPGS_MODE_IMPLICIT)) >> - stpg = 0; >> - break; >> - case TPGS_STATE_STANDBY: >> - case TPGS_STATE_UNAVAILABLE: >> - stpg = 1; >> - break; >> - case TPGS_STATE_OFFLINE: >> - err = SCSI_DH_IO; >> - break; >> - case TPGS_STATE_TRANSITIONING: >> - err = SCSI_DH_RETRY; >> - break; >> - default: >> - break; >> - } >> - } >> - >> - if (stpg) { >> - h->callback_fn = fn; >> - h->callback_data = data; >> - err = submit_stpg(h); >> - if (err == SCSI_DH_OK) >> - return 0; >> - h->callback_fn = h->callback_data = NULL; >> - } >> - >> + err = alua_stpg(sdev, h); >> + if (err == SCSI_DH_RETRY) >> + err = alua_rtpg(sdev, h, 1); >> out: >> if (fn) >> fn(data, err); > > submit_stpg() now returns DRIVER_BUSY << 24 instead of SCSI_DH_RES_TEMP_UNAVAIL, > so you are changing the return code semantics here as in patch 5/23. That's > fine, but probably should be mentioned in the patch description. > > The removed stpg_endio() code *did* evaluate the SCSI error code, and the code > that has replaced it doesn't exactly do the same thing, so what difference in > behavior are we going to get here? > Correct. Is fixed up with the next version of the patchset. Cheers, Hannes
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 9e2b3af..fd0385e 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -172,76 +172,28 @@ 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)) { - err = alua_check_sense(h->sdev, &sense_hdr); - if (err == ADD_TO_MLQUEUE) { - 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 * * 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; @@ -249,13 +201,17 @@ 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 = h->senselen = 0; - rq->end_io_data = h; + rq->sense_len = 0; + + blk_execute_rq(rq->q, NULL, rq, 1); + if (rq->errors) + err = rq->errors; + + blk_put_request(rq); - blk_execute_rq_nowait(rq->q, NULL, rq, 1, stpg_endio); - return SCSI_DH_OK; + return err; } /* @@ -619,6 +575,68 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_ } /* + * alua_stpg - Issue a SET TARGET GROUP STATES command + * + * Issue a SET TARGET GROUP STATES command and evaluate the + * response. Returns SCSI_DH_RETRY per default to trigger + * a re-evaluation of the target group state. + */ +static unsigned alua_stpg(struct scsi_device *sdev, struct alua_dh_data *h) +{ + 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: + if ((h->flags & ALUA_OPTIMIZE_STPG) && + !h->pref && + (h->tpgs & TPGS_MODE_IMPLICIT)) + return SCSI_DH_OK; + break; + case TPGS_STATE_STANDBY: + case TPGS_STATE_UNAVAILABLE: + break; + case TPGS_STATE_OFFLINE: + return SCSI_DH_IO; + break; + case TPGS_STATE_TRANSITIONING: + break; + default: + sdev_printk(KERN_INFO, sdev, + "%s: stpg failed, unhandled TPGS state %d", + ALUA_DH_NAME, h->state); + return SCSI_DH_NOSYS; + break; + } + /* Set state to transitioning */ + h->state = TPGS_STATE_TRANSITIONING; + retval = submit_stpg(sdev, h->group_id, h->sense); + + 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); + } + } + /* Retry RTPG */ + return SCSI_DH_RETRY; +} + +/* * alua_initialize - Initialize ALUA state * @sdev: the device to be initialized * @@ -695,7 +713,6 @@ static int alua_activate(struct scsi_device *sdev, { struct alua_dh_data *h = sdev->handler_data; int err = SCSI_DH_OK; - int stpg = 0; err = alua_rtpg(sdev, h, 1); if (err != SCSI_DH_OK) @@ -704,39 +721,9 @@ static int alua_activate(struct scsi_device *sdev, if (optimize_stpg) h->flags |= ALUA_OPTIMIZE_STPG; - if (h->tpgs & TPGS_MODE_EXPLICIT) { - switch (h->state) { - case TPGS_STATE_NONOPTIMIZED: - stpg = 1; - if ((h->flags & ALUA_OPTIMIZE_STPG) && - (!h->pref) && - (h->tpgs & TPGS_MODE_IMPLICIT)) - stpg = 0; - break; - case TPGS_STATE_STANDBY: - case TPGS_STATE_UNAVAILABLE: - stpg = 1; - break; - case TPGS_STATE_OFFLINE: - err = SCSI_DH_IO; - break; - case TPGS_STATE_TRANSITIONING: - err = SCSI_DH_RETRY; - break; - default: - break; - } - } - - if (stpg) { - h->callback_fn = fn; - h->callback_data = data; - err = submit_stpg(h); - if (err == SCSI_DH_OK) - return 0; - h->callback_fn = h->callback_data = NULL; - } - + err = alua_stpg(sdev, h); + if (err == SCSI_DH_RETRY) + err = alua_rtpg(sdev, h, 1); out: if (fn) fn(data, err);
We should be issuing STPG synchronously as we need to evaluate the return code on failure. Signed-off-by: Hannes Reinecke <hare@suse.de> --- drivers/scsi/device_handler/scsi_dh_alua.c | 179 +++++++++++++---------------- 1 file changed, 83 insertions(+), 96 deletions(-)