* [PATCHv4 01/23] scsi_dh_alua: Pass buffer as function argument
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
@ 2016-01-19 8:21 ` Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 02/23] scsi_dh_alua: separate out alua_stpg() Hannes Reinecke
` (22 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:21 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
Pass in the buffer as a function argument for submit_rtpg().
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 5a328bf..df71e85 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -135,12 +135,13 @@ static struct request *get_alua_req(struct scsi_device *sdev,
* submit_rtpg - Issue a REPORT TARGET GROUP STATES command
* @sdev: sdev the command should be sent to
*/
-static unsigned submit_rtpg(struct scsi_device *sdev, struct alua_dh_data *h)
+static unsigned submit_rtpg(struct scsi_device *sdev, unsigned char *buff,
+ int bufflen, unsigned char *sense, int flags)
{
struct request *rq;
int err = 0;
- rq = get_alua_req(sdev, h->buff, h->bufflen, READ);
+ rq = get_alua_req(sdev, buff, bufflen, READ);
if (!rq) {
err = DRIVER_BUSY << 24;
goto done;
@@ -148,14 +149,14 @@ static unsigned submit_rtpg(struct scsi_device *sdev, struct alua_dh_data *h)
/* Prepare the command. */
rq->cmd[0] = MAINTENANCE_IN;
- if (!(h->flags & ALUA_RTPG_EXT_HDR_UNSUPP))
+ if (!(flags & ALUA_RTPG_EXT_HDR_UNSUPP))
rq->cmd[1] = MI_REPORT_TARGET_PGS | MI_EXT_HDR_PARAM_FMT;
else
rq->cmd[1] = MI_REPORT_TARGET_PGS;
- put_unaligned_be32(h->bufflen, &rq->cmd[6]);
+ put_unaligned_be32(bufflen, &rq->cmd[6]);
rq->cmd_len = COMMAND_SIZE(MAINTENANCE_IN);
- rq->sense = h->sense;
+ rq->sense = sense;
memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
rq->sense_len = 0;
@@ -446,7 +447,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
expiry = round_jiffies_up(jiffies + h->transition_tmo * HZ);
retry:
- retval = submit_rtpg(sdev, h);
+ retval = submit_rtpg(sdev, h->buff, h->bufflen, h->sense, h->flags);
if (retval) {
if (!scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE,
&sense_hdr)) {
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 02/23] scsi_dh_alua: separate out alua_stpg()
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 01/23] scsi_dh_alua: Pass buffer as function argument Hannes Reinecke
@ 2016-01-19 8:21 ` Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 03/23] scsi_dh_alua: Make stpg synchronous Hannes Reinecke
` (21 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:21 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
Separate out SET TARGET PORT GROUP functionality into a separate
function alua_stpg().
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 95 +++++++++++++++++++-----------
1 file changed, 61 insertions(+), 34 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index df71e85..7c66e4a 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -579,6 +579,65 @@ 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 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.
+ */
+static unsigned alua_stpg(struct scsi_device *sdev, struct alua_dh_data *h,
+ activate_complete fn, void *data)
+{
+ int err = SCSI_DH_OK;
+ int stpg = 0;
+
+ if (!(h->tpgs & TPGS_MODE_EXPLICIT))
+ /* Only implicit ALUA supported */
+ goto out;
+
+ 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)
+ h->callback_fn = h->callback_data = NULL;
+ else
+ fn = NULL;
+ }
+out:
+ if (fn)
+ fn(data, err);
+
+ return err;
+}
+
+/*
* alua_initialize - Initialize ALUA state
* @sdev: the device to be initialized
*
@@ -655,7 +714,6 @@ 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)
@@ -664,41 +722,10 @@ 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, fn, data);
out:
- if (fn)
+ if (err != SCSI_DH_OK && fn)
fn(data, err);
return 0;
}
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 03/23] scsi_dh_alua: Make stpg synchronous
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 01/23] scsi_dh_alua: Pass buffer as function argument Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 02/23] scsi_dh_alua: separate out alua_stpg() Hannes Reinecke
@ 2016-01-19 8:21 ` Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 04/23] scsi_dh_alua: call alua_rtpg() if stpg fails Hannes Reinecke
` (20 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:21 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
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: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 156 ++++++++++-------------------
1 file changed, 55 insertions(+), 101 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 7c66e4a..609691f 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
*
* 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 +533,63 @@ 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 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;
+ return SCSI_DH_IO;
break;
case TPGS_STATE_TRANSITIONING:
- err = SCSI_DH_RETRY;
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 (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 +677,9 @@ 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;
}
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 04/23] scsi_dh_alua: call alua_rtpg() if stpg fails
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (2 preceding siblings ...)
2016-01-19 8:21 ` [PATCHv4 03/23] scsi_dh_alua: Make stpg synchronous Hannes Reinecke
@ 2016-01-19 8:21 ` Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 05/23] scsi_dh_alua: switch to scsi_execute_req_flags() Hannes Reinecke
` (19 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:21 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
If the call to SET TARGET PORT GROUPS fails we have no idea what
state the array is left in, so we need to issue a call to
REPORT TARGET PORT GROUPS in these cases.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 609691f..ba3d23e 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -678,6 +678,8 @@ static int alua_activate(struct scsi_device *sdev,
h->flags |= ALUA_OPTIMIZE_STPG;
err = alua_stpg(sdev, h);
+ if (err == SCSI_DH_RETRY)
+ err = alua_rtpg(sdev, h, 1);
out:
if (fn)
fn(data, err);
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 05/23] scsi_dh_alua: switch to scsi_execute_req_flags()
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (3 preceding siblings ...)
2016-01-19 8:21 ` [PATCHv4 04/23] scsi_dh_alua: call alua_rtpg() if stpg fails Hannes Reinecke
@ 2016-01-19 8:21 ` Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 06/23] scsi_dh_alua: allocate RTPG buffer separately Hannes Reinecke
` (18 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:21 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
All commands are issued synchronously, so no need to open-code
scsi_execute_req_flags() anymore. And we can get rid of the
static sense code structure element. scsi_execute_req_flags()
will be setting REQ_QUIET and REQ_PREEMPT, but that is
perfectly fine as we're evaluating and logging any errors
ourselves and we really need to send the command even if
the device is quiesced.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 125 +++++++++--------------------
1 file changed, 36 insertions(+), 89 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index ba3d23e..063c03a 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -75,7 +75,6 @@ struct alua_dh_data {
unsigned char *buff;
int bufflen;
unsigned char transition_tmo;
- unsigned char sense[SCSI_SENSE_BUFFERSIZE];
struct scsi_device *sdev;
activate_complete callback_fn;
void *callback_data;
@@ -101,71 +100,30 @@ static int realloc_buffer(struct alua_dh_data *h, unsigned len)
return 0;
}
-static struct request *get_alua_req(struct scsi_device *sdev,
- void *buffer, unsigned buflen, int rw)
-{
- struct request *rq;
- struct request_queue *q = sdev->request_queue;
-
- rq = blk_get_request(q, rw, GFP_NOIO);
-
- if (IS_ERR(rq)) {
- sdev_printk(KERN_INFO, sdev,
- "%s: blk_get_request failed\n", __func__);
- return NULL;
- }
- blk_rq_set_block_pc(rq);
-
- if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_NOIO)) {
- blk_put_request(rq);
- sdev_printk(KERN_INFO, sdev,
- "%s: blk_rq_map_kern failed\n", __func__);
- return NULL;
- }
-
- rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
- REQ_FAILFAST_DRIVER;
- rq->retries = ALUA_FAILOVER_RETRIES;
- rq->timeout = ALUA_FAILOVER_TIMEOUT * HZ;
-
- return rq;
-}
-
/*
* submit_rtpg - Issue a REPORT TARGET GROUP STATES command
* @sdev: sdev the command should be sent to
*/
-static unsigned submit_rtpg(struct scsi_device *sdev, unsigned char *buff,
- int bufflen, unsigned char *sense, int flags)
+static int submit_rtpg(struct scsi_device *sdev, unsigned char *buff,
+ int bufflen, struct scsi_sense_hdr *sshdr, int flags)
{
- struct request *rq;
- int err = 0;
-
- rq = get_alua_req(sdev, buff, bufflen, READ);
- if (!rq) {
- err = DRIVER_BUSY << 24;
- goto done;
- }
+ u8 cdb[COMMAND_SIZE(MAINTENANCE_IN)];
+ int req_flags = REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
+ REQ_FAILFAST_DRIVER;
/* Prepare the command. */
- rq->cmd[0] = MAINTENANCE_IN;
+ memset(cdb, 0x0, COMMAND_SIZE(MAINTENANCE_IN));
+ cdb[0] = MAINTENANCE_IN;
if (!(flags & ALUA_RTPG_EXT_HDR_UNSUPP))
- rq->cmd[1] = MI_REPORT_TARGET_PGS | MI_EXT_HDR_PARAM_FMT;
+ cdb[1] = MI_REPORT_TARGET_PGS | MI_EXT_HDR_PARAM_FMT;
else
- rq->cmd[1] = MI_REPORT_TARGET_PGS;
- put_unaligned_be32(bufflen, &rq->cmd[6]);
- rq->cmd_len = COMMAND_SIZE(MAINTENANCE_IN);
-
- rq->sense = sense;
- memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
- rq->sense_len = 0;
-
- blk_execute_rq(rq->q, NULL, rq, 1);
- if (rq->errors)
- err = rq->errors;
- blk_put_request(rq);
-done:
- return err;
+ cdb[1] = MI_REPORT_TARGET_PGS;
+ put_unaligned_be32(bufflen, &cdb[6]);
+
+ return scsi_execute_req_flags(sdev, cdb, DMA_FROM_DEVICE,
+ buff, bufflen, sshdr,
+ ALUA_FAILOVER_TIMEOUT * HZ,
+ ALUA_FAILOVER_RETRIES, NULL, req_flags);
}
/*
@@ -175,40 +133,30 @@ done:
* to 'active/optimized' and let the array firmware figure out
* the states of the remaining groups.
*/
-static unsigned submit_stpg(struct scsi_device *sdev, int group_id,
- unsigned char *sense)
+static int submit_stpg(struct scsi_device *sdev, int group_id,
+ struct scsi_sense_hdr *sshdr)
{
- struct request *rq;
+ u8 cdb[COMMAND_SIZE(MAINTENANCE_OUT)];
unsigned char stpg_data[8];
int stpg_len = 8;
- int err = 0;
+ int req_flags = REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
+ REQ_FAILFAST_DRIVER;
/* Prepare the data buffer */
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, stpg_data, stpg_len, WRITE);
- if (!rq)
- return DRIVER_BUSY << 24;
-
/* Prepare the command. */
- rq->cmd[0] = MAINTENANCE_OUT;
- rq->cmd[1] = MO_SET_TARGET_PGS;
- put_unaligned_be32(stpg_len, &rq->cmd[6]);
- rq->cmd_len = COMMAND_SIZE(MAINTENANCE_OUT);
-
- rq->sense = sense;
- memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
- rq->sense_len = 0;
-
- blk_execute_rq(rq->q, NULL, rq, 1);
- if (rq->errors)
- err = rq->errors;
-
- blk_put_request(rq);
-
- return err;
+ memset(cdb, 0x0, COMMAND_SIZE(MAINTENANCE_OUT));
+ cdb[0] = MAINTENANCE_OUT;
+ cdb[1] = MO_SET_TARGET_PGS;
+ put_unaligned_be32(stpg_len, &cdb[6]);
+
+ return scsi_execute_req_flags(sdev, cdb, DMA_TO_DEVICE,
+ stpg_data, stpg_len,
+ sshdr, ALUA_FAILOVER_TIMEOUT * HZ,
+ ALUA_FAILOVER_RETRIES, NULL, req_flags);
}
/*
@@ -398,14 +346,14 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
expiry = round_jiffies_up(jiffies + h->transition_tmo * HZ);
retry:
- retval = submit_rtpg(sdev, h->buff, h->bufflen, h->sense, h->flags);
+ retval = submit_rtpg(sdev, h->buff, h->bufflen, &sense_hdr, h->flags);
+
if (retval) {
- if (!scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE,
- &sense_hdr)) {
+ if (!scsi_sense_valid(&sense_hdr)) {
sdev_printk(KERN_INFO, sdev,
"%s: rtpg failed, result %d\n",
ALUA_DH_NAME, retval);
- if (driver_byte(retval) == DRIVER_BUSY)
+ if (driver_byte(retval) == DRIVER_ERROR)
return SCSI_DH_DEV_TEMP_BUSY;
return SCSI_DH_IO;
}
@@ -572,15 +520,14 @@ static unsigned alua_stpg(struct scsi_device *sdev, struct alua_dh_data *h)
}
/* Set state to transitioning */
h->state = TPGS_STATE_TRANSITIONING;
- retval = submit_stpg(sdev, h->group_id, h->sense);
+ retval = submit_stpg(sdev, h->group_id, &sense_hdr);
if (retval) {
- if (!scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE,
- &sense_hdr)) {
+ if (!scsi_sense_valid(&sense_hdr)) {
sdev_printk(KERN_INFO, sdev,
"%s: stpg failed, result %d",
ALUA_DH_NAME, retval);
- if (driver_byte(retval) == DRIVER_BUSY)
+ if (driver_byte(retval) == DRIVER_ERROR)
return SCSI_DH_DEV_TEMP_BUSY;
} else {
sdev_printk(KERN_INFO, h->sdev, "%s: stpg failed\n",
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 06/23] scsi_dh_alua: allocate RTPG buffer separately
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (4 preceding siblings ...)
2016-01-19 8:21 ` [PATCHv4 05/23] scsi_dh_alua: switch to scsi_execute_req_flags() Hannes Reinecke
@ 2016-01-19 8:21 ` Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 07/23] scsi_dh_alua: Use separate alua_port_group structure Hannes Reinecke
` (17 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:21 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
The RTPG buffer will only evaluated within alua_rtpg(),
so we can allocate it locally there and avoid having to
put it into the global structure.
Reviewed-by: Ewan Milne <emilne@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 57 ++++++++++++------------------
1 file changed, 23 insertions(+), 34 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 063c03a..49dea42 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -56,7 +56,7 @@
#define TPGS_MODE_IMPLICIT 0x1
#define TPGS_MODE_EXPLICIT 0x2
-#define ALUA_INQUIRY_SIZE 36
+#define ALUA_RTPG_SIZE 128
#define ALUA_FAILOVER_TIMEOUT 60
#define ALUA_FAILOVER_RETRIES 5
@@ -71,9 +71,6 @@ struct alua_dh_data {
int state;
int pref;
unsigned flags; /* used for optimizing STPG */
- unsigned char inq[ALUA_INQUIRY_SIZE];
- unsigned char *buff;
- int bufflen;
unsigned char transition_tmo;
struct scsi_device *sdev;
activate_complete callback_fn;
@@ -85,21 +82,6 @@ struct alua_dh_data {
static char print_alua_state(int);
-static int realloc_buffer(struct alua_dh_data *h, unsigned len)
-{
- if (h->buff && h->buff != h->inq)
- kfree(h->buff);
-
- h->buff = kmalloc(len, GFP_NOIO);
- if (!h->buff) {
- h->buff = h->inq;
- h->bufflen = ALUA_INQUIRY_SIZE;
- return 1;
- }
- h->bufflen = len;
- return 0;
-}
-
/*
* submit_rtpg - Issue a REPORT TARGET GROUP STATES command
* @sdev: sdev the command should be sent to
@@ -333,8 +315,8 @@ static int alua_check_sense(struct scsi_device *sdev,
static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_for_transition)
{
struct scsi_sense_hdr sense_hdr;
- int len, k, off, valid_states = 0;
- unsigned char *ucp;
+ int len, k, off, valid_states = 0, bufflen = ALUA_RTPG_SIZE;
+ unsigned char *ucp, *buff;
unsigned err, retval;
unsigned long expiry, interval = 0;
unsigned int tpg_desc_tbl_off;
@@ -345,14 +327,19 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
else
expiry = round_jiffies_up(jiffies + h->transition_tmo * HZ);
+ buff = kzalloc(bufflen, GFP_KERNEL);
+ if (!buff)
+ return SCSI_DH_DEV_TEMP_BUSY;
+
retry:
- retval = submit_rtpg(sdev, h->buff, h->bufflen, &sense_hdr, h->flags);
+ retval = submit_rtpg(sdev, buff, bufflen, &sense_hdr, h->flags);
if (retval) {
if (!scsi_sense_valid(&sense_hdr)) {
sdev_printk(KERN_INFO, sdev,
"%s: rtpg failed, result %d\n",
ALUA_DH_NAME, retval);
+ kfree(buff);
if (driver_byte(retval) == DRIVER_ERROR)
return SCSI_DH_DEV_TEMP_BUSY;
return SCSI_DH_IO;
@@ -390,14 +377,18 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
sdev_printk(KERN_ERR, sdev, "%s: rtpg failed\n",
ALUA_DH_NAME);
scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr);
+ kfree(buff);
return SCSI_DH_IO;
}
- len = get_unaligned_be32(&h->buff[0]) + 4;
+ len = get_unaligned_be32(&buff[0]) + 4;
- if (len > h->bufflen) {
+ if (len > bufflen) {
/* Resubmit with the correct length */
- if (realloc_buffer(h, len)) {
+ kfree(buff);
+ bufflen = len;
+ buff = kmalloc(bufflen, GFP_KERNEL);
+ if (!buff) {
sdev_printk(KERN_WARNING, sdev,
"%s: kmalloc buffer failed\n",__func__);
/* Temporary failure, bypass */
@@ -407,24 +398,25 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
}
orig_transition_tmo = h->transition_tmo;
- if ((h->buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR && h->buff[5] != 0)
- h->transition_tmo = h->buff[5];
+ if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR && buff[5] != 0)
+ h->transition_tmo = buff[5];
else
h->transition_tmo = ALUA_FAILOVER_TIMEOUT;
- if (wait_for_transition && (orig_transition_tmo != h->transition_tmo)) {
+ if (wait_for_transition &&
+ (orig_transition_tmo != h->transition_tmo)) {
sdev_printk(KERN_INFO, sdev,
"%s: transition timeout set to %d seconds\n",
ALUA_DH_NAME, h->transition_tmo);
expiry = jiffies + h->transition_tmo * HZ;
}
- if ((h->buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR)
+ if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR)
tpg_desc_tbl_off = 8;
else
tpg_desc_tbl_off = 4;
- for (k = tpg_desc_tbl_off, ucp = h->buff + tpg_desc_tbl_off;
+ for (k = tpg_desc_tbl_off, ucp = buff + tpg_desc_tbl_off;
k < len;
k += off, ucp += off) {
@@ -474,6 +466,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
err = SCSI_DH_OK;
break;
}
+ kfree(buff);
return err;
}
@@ -672,8 +665,6 @@ static int alua_bus_attach(struct scsi_device *sdev)
h->state = TPGS_STATE_OPTIMIZED;
h->group_id = -1;
h->rel_port = -1;
- h->buff = h->inq;
- h->bufflen = ALUA_INQUIRY_SIZE;
h->sdev = sdev;
err = alua_initialize(sdev, h);
@@ -695,8 +686,6 @@ static void alua_bus_detach(struct scsi_device *sdev)
{
struct alua_dh_data *h = sdev->handler_data;
- if (h->buff && h->inq != h->buff)
- kfree(h->buff);
sdev->handler_data = NULL;
kfree(h);
}
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 07/23] scsi_dh_alua: Use separate alua_port_group structure
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (5 preceding siblings ...)
2016-01-19 8:21 ` [PATCHv4 06/23] scsi_dh_alua: allocate RTPG buffer separately Hannes Reinecke
@ 2016-01-19 8:21 ` Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 08/23] scsi_dh_alua: use unique device id Hannes Reinecke
` (16 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:21 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
The port group needs to be a separate structure as several
LUNs might belong to the same group.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 183 ++++++++++++++++++++---------
include/scsi/scsi_dh.h | 1 +
2 files changed, 130 insertions(+), 54 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 49dea42..14b4ca6 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -64,14 +64,24 @@
#define ALUA_OPTIMIZE_STPG 1
#define ALUA_RTPG_EXT_HDR_UNSUPP 2
-struct alua_dh_data {
+static LIST_HEAD(port_group_list);
+static DEFINE_SPINLOCK(port_group_lock);
+
+struct alua_port_group {
+ struct kref kref;
+ struct list_head node;
int group_id;
- int rel_port;
int tpgs;
int state;
int pref;
unsigned flags; /* used for optimizing STPG */
unsigned char transition_tmo;
+};
+
+struct alua_dh_data {
+ struct alua_port_group *pg;
+ int group_id;
+ int rel_port;
struct scsi_device *sdev;
activate_complete callback_fn;
void *callback_data;
@@ -82,6 +92,17 @@ struct alua_dh_data {
static char print_alua_state(int);
+static void release_port_group(struct kref *kref)
+{
+ struct alua_port_group *pg;
+
+ pg = container_of(kref, struct alua_port_group, kref);
+ spin_lock(&port_group_lock);
+ list_del(&pg->node);
+ spin_unlock(&port_group_lock);
+ kfree(pg);
+}
+
/*
* submit_rtpg - Issue a REPORT TARGET GROUP STATES command
* @sdev: sdev the command should be sent to
@@ -142,6 +163,35 @@ static int submit_stpg(struct scsi_device *sdev, int group_id,
}
/*
+ * alua_alloc_pg - Allocate a new port_group structure
+ * @sdev: scsi device
+ * @h: alua device_handler data
+ * @group_id: port group id
+ *
+ * Allocate a new port_group structure for a given
+ * device.
+ */
+struct alua_port_group *alua_alloc_pg(struct scsi_device *sdev,
+ int group_id, int tpgs)
+{
+ struct alua_port_group *pg;
+
+ pg = kzalloc(sizeof(struct alua_port_group), GFP_KERNEL);
+ if (!pg)
+ return NULL;
+
+ pg->group_id = group_id;
+ pg->tpgs = tpgs;
+ pg->state = TPGS_STATE_OPTIMIZED;
+ kref_init(&pg->kref);
+ spin_lock(&port_group_lock);
+ list_add(&pg->node, &port_group_list);
+ spin_unlock(&port_group_lock);
+
+ return pg;
+}
+
+/*
* alua_check_tpgs - Evaluate TPGS setting
* @sdev: device to be checked
*
@@ -216,7 +266,6 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h)
ALUA_DH_NAME);
return SCSI_DH_DEV_UNSUPP;
}
- h->state = TPGS_STATE_OPTIMIZED;
h->group_id = group_id;
sdev_printk(KERN_INFO, sdev,
@@ -312,7 +361,7 @@ static int alua_check_sense(struct scsi_device *sdev,
* Returns SCSI_DH_DEV_OFFLINED if the path is
* found to be unusable.
*/
-static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_for_transition)
+static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg, int wait_for_transition)
{
struct scsi_sense_hdr sense_hdr;
int len, k, off, valid_states = 0, bufflen = ALUA_RTPG_SIZE;
@@ -322,17 +371,17 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
unsigned int tpg_desc_tbl_off;
unsigned char orig_transition_tmo;
- if (!h->transition_tmo)
+ if (!pg->transition_tmo)
expiry = round_jiffies_up(jiffies + ALUA_FAILOVER_TIMEOUT * HZ);
else
- expiry = round_jiffies_up(jiffies + h->transition_tmo * HZ);
+ expiry = round_jiffies_up(jiffies + pg->transition_tmo * HZ);
buff = kzalloc(bufflen, GFP_KERNEL);
if (!buff)
return SCSI_DH_DEV_TEMP_BUSY;
retry:
- retval = submit_rtpg(sdev, buff, bufflen, &sense_hdr, h->flags);
+ retval = submit_rtpg(sdev, buff, bufflen, &sense_hdr, pg->flags);
if (retval) {
if (!scsi_sense_valid(&sense_hdr)) {
@@ -353,10 +402,10 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
* The retry without rtpg_ext_hdr_req set
* handles this.
*/
- if (!(h->flags & ALUA_RTPG_EXT_HDR_UNSUPP) &&
+ if (!(pg->flags & ALUA_RTPG_EXT_HDR_UNSUPP) &&
sense_hdr.sense_key == ILLEGAL_REQUEST &&
sense_hdr.asc == 0x24 && sense_hdr.ascq == 0) {
- h->flags |= ALUA_RTPG_EXT_HDR_UNSUPP;
+ pg->flags |= ALUA_RTPG_EXT_HDR_UNSUPP;
goto retry;
}
/*
@@ -397,18 +446,18 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
goto retry;
}
- orig_transition_tmo = h->transition_tmo;
+ orig_transition_tmo = pg->transition_tmo;
if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR && buff[5] != 0)
- h->transition_tmo = buff[5];
+ pg->transition_tmo = buff[5];
else
- h->transition_tmo = ALUA_FAILOVER_TIMEOUT;
+ pg->transition_tmo = ALUA_FAILOVER_TIMEOUT;
if (wait_for_transition &&
- (orig_transition_tmo != h->transition_tmo)) {
+ (orig_transition_tmo != pg->transition_tmo)) {
sdev_printk(KERN_INFO, sdev,
"%s: transition timeout set to %d seconds\n",
- ALUA_DH_NAME, h->transition_tmo);
- expiry = jiffies + h->transition_tmo * HZ;
+ ALUA_DH_NAME, pg->transition_tmo);
+ expiry = jiffies + pg->transition_tmo * HZ;
}
if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR)
@@ -420,9 +469,9 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
k < len;
k += off, ucp += off) {
- if (h->group_id == get_unaligned_be16(&ucp[2])) {
- h->state = ucp[0] & 0x0f;
- h->pref = ucp[0] >> 7;
+ if (pg->group_id == get_unaligned_be16(&ucp[2])) {
+ pg->state = ucp[0] & 0x0f;
+ pg->pref = ucp[0] >> 7;
valid_states = ucp[1];
}
off = 8 + (ucp[7] * 4);
@@ -430,8 +479,8 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
sdev_printk(KERN_INFO, sdev,
"%s: port group %02x state %c %s supports %c%c%c%c%c%c%c\n",
- ALUA_DH_NAME, h->group_id, print_alua_state(h->state),
- h->pref ? "preferred" : "non-preferred",
+ ALUA_DH_NAME, pg->group_id, print_alua_state(pg->state),
+ pg->pref ? "preferred" : "non-preferred",
valid_states&TPGS_SUPPORT_TRANSITION?'T':'t',
valid_states&TPGS_SUPPORT_OFFLINE?'O':'o',
valid_states&TPGS_SUPPORT_LBA_DEPENDENT?'L':'l',
@@ -440,7 +489,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
valid_states&TPGS_SUPPORT_NONOPTIMIZED?'N':'n',
valid_states&TPGS_SUPPORT_OPTIMIZED?'A':'a');
- switch (h->state) {
+ switch (pg->state) {
case TPGS_STATE_TRANSITIONING:
if (wait_for_transition) {
if (time_before(jiffies, expiry)) {
@@ -455,7 +504,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
}
/* Transitioning time exceeded, set port to standby */
- h->state = TPGS_STATE_STANDBY;
+ pg->state = TPGS_STATE_STANDBY;
break;
case TPGS_STATE_OFFLINE:
/* Path unusable */
@@ -478,22 +527,22 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, int wait_
* 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)
+static unsigned alua_stpg(struct scsi_device *sdev, struct alua_port_group *pg)
{
int retval;
struct scsi_sense_hdr sense_hdr;
- if (!(h->tpgs & TPGS_MODE_EXPLICIT)) {
+ if (!(pg->tpgs & TPGS_MODE_EXPLICIT)) {
/* Only implicit ALUA supported, retry */
return SCSI_DH_RETRY;
}
- switch (h->state) {
+ switch (pg->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))
+ if ((pg->flags & ALUA_OPTIMIZE_STPG) &&
+ !pg->pref &&
+ (pg->tpgs & TPGS_MODE_IMPLICIT))
return SCSI_DH_OK;
break;
case TPGS_STATE_STANDBY:
@@ -507,13 +556,13 @@ static unsigned alua_stpg(struct scsi_device *sdev, struct alua_dh_data *h)
default:
sdev_printk(KERN_INFO, sdev,
"%s: stpg failed, unhandled TPGS state %d",
- ALUA_DH_NAME, h->state);
+ ALUA_DH_NAME, pg->state);
return SCSI_DH_NOSYS;
break;
}
/* Set state to transitioning */
- h->state = TPGS_STATE_TRANSITIONING;
- retval = submit_stpg(sdev, h->group_id, &sense_hdr);
+ pg->state = TPGS_STATE_TRANSITIONING;
+ retval = submit_stpg(sdev, pg->group_id, &sense_hdr);
if (retval) {
if (!scsi_sense_valid(&sense_hdr)) {
@@ -523,7 +572,7 @@ static unsigned alua_stpg(struct scsi_device *sdev, struct alua_dh_data *h)
if (driver_byte(retval) == DRIVER_ERROR)
return SCSI_DH_DEV_TEMP_BUSY;
} else {
- sdev_printk(KERN_INFO, h->sdev, "%s: stpg failed\n",
+ sdev_printk(KERN_INFO, sdev, "%s: stpg failed\n",
ALUA_DH_NAME);
scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr);
}
@@ -541,20 +590,24 @@ static unsigned alua_stpg(struct scsi_device *sdev, struct alua_dh_data *h)
*/
static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h)
{
- int err = SCSI_DH_DEV_UNSUPP;
+ int err = SCSI_DH_DEV_UNSUPP, tpgs;
- h->tpgs = alua_check_tpgs(sdev);
- if (h->tpgs == TPGS_MODE_NONE)
+ tpgs = alua_check_tpgs(sdev);
+ if (tpgs == TPGS_MODE_NONE)
goto out;
err = alua_check_vpd(sdev, h);
if (err != SCSI_DH_OK)
goto out;
- err = alua_rtpg(sdev, h, 0);
- if (err != SCSI_DH_OK)
+ h->pg = alua_alloc_pg(sdev, h->group_id, tpgs);
+ if (!h->pg) {
+ err = SCSI_DH_NOMEM;
goto out;
-
+ }
+ kref_get(&h->pg->kref);
+ err = alua_rtpg(sdev, h->pg, 0);
+ kref_put(&h->pg->kref, release_port_group);
out:
return err;
}
@@ -570,6 +623,7 @@ out:
static int alua_set_params(struct scsi_device *sdev, const char *params)
{
struct alua_dh_data *h = sdev->handler_data;
+ struct alua_port_group *pg = NULL;
unsigned int optimize = 0, argc;
const char *p = params;
int result = SCSI_DH_OK;
@@ -582,10 +636,14 @@ static int alua_set_params(struct scsi_device *sdev, const char *params)
if ((sscanf(p, "%u", &optimize) != 1) || (optimize > 1))
return -EINVAL;
+ pg = h->pg;
+ if (!pg)
+ return -ENXIO;
+
if (optimize)
- h->flags |= ALUA_OPTIMIZE_STPG;
+ pg->flags |= ALUA_OPTIMIZE_STPG;
else
- h->flags &= ~ALUA_OPTIMIZE_STPG;
+ pg->flags |= ~ALUA_OPTIMIZE_STPG;
return result;
}
@@ -610,16 +668,23 @@ static int alua_activate(struct scsi_device *sdev,
struct alua_dh_data *h = sdev->handler_data;
int err = SCSI_DH_OK;
- err = alua_rtpg(sdev, h, 1);
- if (err != SCSI_DH_OK)
+ if (!h->pg)
goto out;
+ kref_get(&h->pg->kref);
+
if (optimize_stpg)
- h->flags |= ALUA_OPTIMIZE_STPG;
+ h->pg->flags |= ALUA_OPTIMIZE_STPG;
- err = alua_stpg(sdev, h);
+ err = alua_rtpg(sdev, h->pg, 1);
+ if (err != SCSI_DH_OK) {
+ kref_put(&h->pg->kref, release_port_group);
+ goto out;
+ }
+ err = alua_stpg(sdev, h->pg);
if (err == SCSI_DH_RETRY)
- err = alua_rtpg(sdev, h, 1);
+ err = alua_rtpg(sdev, h->pg, 1);
+ kref_put(&h->pg->kref, release_port_group);
out:
if (fn)
fn(data, err);
@@ -635,13 +700,19 @@ out:
static int alua_prep_fn(struct scsi_device *sdev, struct request *req)
{
struct alua_dh_data *h = sdev->handler_data;
+ int state;
int ret = BLKPREP_OK;
- if (h->state == TPGS_STATE_TRANSITIONING)
+ if (!h->pg)
+ return ret;
+ kref_get(&h->pg->kref);
+ state = h->pg->state;
+ kref_put(&h->pg->kref, release_port_group);
+ if (state == TPGS_STATE_TRANSITIONING)
ret = BLKPREP_DEFER;
- else if (h->state != TPGS_STATE_OPTIMIZED &&
- h->state != TPGS_STATE_NONOPTIMIZED &&
- h->state != TPGS_STATE_LBA_DEPENDENT) {
+ else if (state != TPGS_STATE_OPTIMIZED &&
+ state != TPGS_STATE_NONOPTIMIZED &&
+ state != TPGS_STATE_LBA_DEPENDENT) {
ret = BLKPREP_KILL;
req->cmd_flags |= REQ_QUIET;
}
@@ -656,18 +727,18 @@ static int alua_prep_fn(struct scsi_device *sdev, struct request *req)
static int alua_bus_attach(struct scsi_device *sdev)
{
struct alua_dh_data *h;
- int err;
+ int err, ret = -EINVAL;
h = kzalloc(sizeof(*h) , GFP_KERNEL);
if (!h)
return -ENOMEM;
- h->tpgs = TPGS_MODE_UNINITIALIZED;
- h->state = TPGS_STATE_OPTIMIZED;
- h->group_id = -1;
+ h->pg = NULL;
h->rel_port = -1;
h->sdev = sdev;
err = alua_initialize(sdev, h);
+ if (err == SCSI_DH_NOMEM)
+ ret = -ENOMEM;
if (err != SCSI_DH_OK && err != SCSI_DH_DEV_OFFLINED)
goto failed;
@@ -675,7 +746,7 @@ static int alua_bus_attach(struct scsi_device *sdev)
return 0;
failed:
kfree(h);
- return -EINVAL;
+ return ret;
}
/*
@@ -686,6 +757,10 @@ static void alua_bus_detach(struct scsi_device *sdev)
{
struct alua_dh_data *h = sdev->handler_data;
+ if (h->pg) {
+ kref_put(&h->pg->kref, release_port_group);
+ h->pg = NULL;
+ }
sdev->handler_data = NULL;
kfree(h);
}
diff --git a/include/scsi/scsi_dh.h b/include/scsi/scsi_dh.h
index 85d7317..7e184c6 100644
--- a/include/scsi/scsi_dh.h
+++ b/include/scsi/scsi_dh.h
@@ -52,6 +52,7 @@ enum {
SCSI_DH_TIMED_OUT,
SCSI_DH_RES_TEMP_UNAVAIL,
SCSI_DH_DEV_OFFLINED,
+ SCSI_DH_NOMEM,
SCSI_DH_NOSYS,
SCSI_DH_DRIVER_MAX,
};
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 08/23] scsi_dh_alua: use unique device id
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (6 preceding siblings ...)
2016-01-19 8:21 ` [PATCHv4 07/23] scsi_dh_alua: Use separate alua_port_group structure Hannes Reinecke
@ 2016-01-19 8:21 ` Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 09/23] scsi_dh_alua: simplify alua_initialize() Hannes Reinecke
` (15 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:21 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
Use scsi_vpd_lun_id() to assign a unique device identification
to the alua port group structure.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 57 +++++++++++++++++++++++++++---
1 file changed, 53 insertions(+), 4 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 14b4ca6..ea0cf9f 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -70,6 +70,8 @@ static DEFINE_SPINLOCK(port_group_lock);
struct alua_port_group {
struct kref kref;
struct list_head node;
+ unsigned char device_id_str[256];
+ int device_id_len;
int group_id;
int tpgs;
int state;
@@ -162,6 +164,26 @@ static int submit_stpg(struct scsi_device *sdev, int group_id,
ALUA_FAILOVER_RETRIES, NULL, req_flags);
}
+struct alua_port_group *alua_find_get_pg(char *id_str, size_t id_size,
+ int group_id)
+{
+ struct alua_port_group *pg;
+
+ list_for_each_entry(pg, &port_group_list, node) {
+ if (pg->group_id != group_id)
+ continue;
+ if (pg->device_id_len != id_size)
+ continue;
+ if (strncmp(pg->device_id_str, id_str, id_size))
+ continue;
+ if (!kref_get_unless_zero(&pg->kref))
+ continue;
+ return pg;
+ }
+
+ return NULL;
+}
+
/*
* alua_alloc_pg - Allocate a new port_group structure
* @sdev: scsi device
@@ -174,17 +196,39 @@ static int submit_stpg(struct scsi_device *sdev, int group_id,
struct alua_port_group *alua_alloc_pg(struct scsi_device *sdev,
int group_id, int tpgs)
{
- struct alua_port_group *pg;
+ struct alua_port_group *pg, *tmp_pg;
pg = kzalloc(sizeof(struct alua_port_group), GFP_KERNEL);
if (!pg)
- return NULL;
+ return ERR_PTR(-ENOMEM);
+ pg->device_id_len = scsi_vpd_lun_id(sdev, pg->device_id_str,
+ sizeof(pg->device_id_str));
+ if (pg->device_id_len <= 0) {
+ /*
+ * Internal error: TPGS supported but no device
+ * identifcation found. Disable ALUA support.
+ */
+ kfree(pg);
+ sdev_printk(KERN_INFO, sdev,
+ "%s: No device descriptors found\n",
+ ALUA_DH_NAME);
+ return ERR_PTR(-ENXIO);
+ }
pg->group_id = group_id;
pg->tpgs = tpgs;
pg->state = TPGS_STATE_OPTIMIZED;
kref_init(&pg->kref);
+
spin_lock(&port_group_lock);
+ tmp_pg = alua_find_get_pg(pg->device_id_str, pg->device_id_len,
+ group_id);
+ if (tmp_pg) {
+ spin_unlock(&port_group_lock);
+ kfree(pg);
+ return tmp_pg;
+ }
+
list_add(&pg->node, &port_group_list);
spin_unlock(&port_group_lock);
@@ -601,10 +645,15 @@ static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h)
goto out;
h->pg = alua_alloc_pg(sdev, h->group_id, tpgs);
- if (!h->pg) {
- err = SCSI_DH_NOMEM;
+ if (PTR_ERR(h->pg)) {
+ if (PTR_ERR(h->pg) == -ENOMEM)
+ err = SCSI_DH_NOMEM;
goto out;
}
+ sdev_printk(KERN_INFO, sdev,
+ "%s: device %s port group %02x rel port %02x\n",
+ ALUA_DH_NAME, h->pg->device_id_str,
+ h->group_id, h->rel_port);
kref_get(&h->pg->kref);
err = alua_rtpg(sdev, h->pg, 0);
kref_put(&h->pg->kref, release_port_group);
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 09/23] scsi_dh_alua: simplify alua_initialize()
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (7 preceding siblings ...)
2016-01-19 8:21 ` [PATCHv4 08/23] scsi_dh_alua: use unique device id Hannes Reinecke
@ 2016-01-19 8:21 ` Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 10/23] revert commit a8e5a2d593cb ("[SCSI] scsi_dh_alua: ALUA handler attach should succeed while TPG is transitioning") Hannes Reinecke
` (14 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:21 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
Rework alua_check_vpd() to use scsi_vpd_get_tpg()
and move the port group selection into the function, too.
With that we can simplify alua_initialize() to just
call alua_check_tpgs() and alua_check_vpd();
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 42 ++++++++++++------------------
1 file changed, 17 insertions(+), 25 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index ea0cf9f..79f5211 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -92,6 +92,7 @@ struct alua_dh_data {
#define ALUA_POLICY_SWITCH_CURRENT 0
#define ALUA_POLICY_SWITCH_ALL 1
+static int alua_rtpg(struct scsi_device *, struct alua_port_group *, int);
static char print_alua_state(int);
static void release_port_group(struct kref *kref)
@@ -294,7 +295,8 @@ static int alua_check_tpgs(struct scsi_device *sdev)
* Extract the relative target port and the target port group
* descriptor from the list of identificators.
*/
-static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h)
+static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h,
+ int tpgs)
{
int rel_port = -1, group_id;
@@ -310,13 +312,21 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h)
ALUA_DH_NAME);
return SCSI_DH_DEV_UNSUPP;
}
- h->group_id = group_id;
+
+ h->pg = alua_alloc_pg(sdev, group_id, tpgs);
+ if (PTR_ERR(h->pg)) {
+ if (PTR_ERR(h->pg) == -ENOMEM)
+ return SCSI_DH_NOMEM;
+ return SCSI_DH_DEV_UNSUPP;
+ }
+ h->rel_port = rel_port;
sdev_printk(KERN_INFO, sdev,
- "%s: port group %02x rel port %02x\n",
- ALUA_DH_NAME, h->group_id, h->rel_port);
+ "%s: device %s port group %02x rel port %02x\n",
+ ALUA_DH_NAME, h->pg->device_id_str,
+ h->group_id, h->rel_port);
- return 0;
+ return alua_rtpg(sdev, h->pg, 0);
}
static char print_alua_state(int state)
@@ -637,27 +647,9 @@ static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h)
int err = SCSI_DH_DEV_UNSUPP, tpgs;
tpgs = alua_check_tpgs(sdev);
- if (tpgs == TPGS_MODE_NONE)
- goto out;
-
- err = alua_check_vpd(sdev, h);
- if (err != SCSI_DH_OK)
- goto out;
+ if (tpgs != TPGS_MODE_NONE)
+ err = alua_check_vpd(sdev, h, tpgs);
- h->pg = alua_alloc_pg(sdev, h->group_id, tpgs);
- if (PTR_ERR(h->pg)) {
- if (PTR_ERR(h->pg) == -ENOMEM)
- err = SCSI_DH_NOMEM;
- goto out;
- }
- sdev_printk(KERN_INFO, sdev,
- "%s: device %s port group %02x rel port %02x\n",
- ALUA_DH_NAME, h->pg->device_id_str,
- h->group_id, h->rel_port);
- kref_get(&h->pg->kref);
- err = alua_rtpg(sdev, h->pg, 0);
- kref_put(&h->pg->kref, release_port_group);
-out:
return err;
}
/*
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 10/23] revert commit a8e5a2d593cb ("[SCSI] scsi_dh_alua: ALUA handler attach should succeed while TPG is transitioning")
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (8 preceding siblings ...)
2016-01-19 8:21 ` [PATCHv4 09/23] scsi_dh_alua: simplify alua_initialize() Hannes Reinecke
@ 2016-01-19 8:21 ` Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 11/23] scsi_dh_alua: move optimize_stpg evaluation Hannes Reinecke
` (13 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:21 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
This reverts commit a8e5a2d593cbfccf530c3382c2c328d2edaa7b66
Obsoleted by the next patch.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 31 ++++++++++++------------------
1 file changed, 12 insertions(+), 19 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 79f5211..560924b 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -92,7 +92,7 @@ struct alua_dh_data {
#define ALUA_POLICY_SWITCH_CURRENT 0
#define ALUA_POLICY_SWITCH_ALL 1
-static int alua_rtpg(struct scsi_device *, struct alua_port_group *, int);
+static int alua_rtpg(struct scsi_device *, struct alua_port_group *);
static char print_alua_state(int);
static void release_port_group(struct kref *kref)
@@ -326,7 +326,7 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h,
ALUA_DH_NAME, h->pg->device_id_str,
h->group_id, h->rel_port);
- return alua_rtpg(sdev, h->pg, 0);
+ return alua_rtpg(sdev, h->pg);
}
static char print_alua_state(int state)
@@ -409,13 +409,12 @@ static int alua_check_sense(struct scsi_device *sdev,
/*
* alua_rtpg - Evaluate REPORT TARGET GROUP STATES
* @sdev: the device to be evaluated.
- * @wait_for_transition: if nonzero, wait ALUA_FAILOVER_TIMEOUT seconds for device to exit transitioning state
*
* Evaluate the Target Port Group State.
* Returns SCSI_DH_DEV_OFFLINED if the path is
* found to be unusable.
*/
-static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg, int wait_for_transition)
+static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg)
{
struct scsi_sense_hdr sense_hdr;
int len, k, off, valid_states = 0, bufflen = ALUA_RTPG_SIZE;
@@ -506,8 +505,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg, int w
else
pg->transition_tmo = ALUA_FAILOVER_TIMEOUT;
- if (wait_for_transition &&
- (orig_transition_tmo != pg->transition_tmo)) {
+ if (orig_transition_tmo != pg->transition_tmo) {
sdev_printk(KERN_INFO, sdev,
"%s: transition timeout set to %d seconds\n",
ALUA_DH_NAME, pg->transition_tmo);
@@ -545,19 +543,14 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg, int w
switch (pg->state) {
case TPGS_STATE_TRANSITIONING:
- if (wait_for_transition) {
- if (time_before(jiffies, expiry)) {
- /* State transition, retry */
- interval += 2000;
- msleep(interval);
- goto retry;
- }
- err = SCSI_DH_RETRY;
- } else {
- err = SCSI_DH_OK;
+ if (time_before(jiffies, expiry)) {
+ /* State transition, retry */
+ interval += 2000;
+ msleep(interval);
+ goto retry;
}
-
/* Transitioning time exceeded, set port to standby */
+ err = SCSI_DH_RETRY;
pg->state = TPGS_STATE_STANDBY;
break;
case TPGS_STATE_OFFLINE:
@@ -717,14 +710,14 @@ static int alua_activate(struct scsi_device *sdev,
if (optimize_stpg)
h->pg->flags |= ALUA_OPTIMIZE_STPG;
- err = alua_rtpg(sdev, h->pg, 1);
+ err = alua_rtpg(sdev, h->pg);
if (err != SCSI_DH_OK) {
kref_put(&h->pg->kref, release_port_group);
goto out;
}
err = alua_stpg(sdev, h->pg);
if (err == SCSI_DH_RETRY)
- err = alua_rtpg(sdev, h->pg, 1);
+ err = alua_rtpg(sdev, h->pg);
kref_put(&h->pg->kref, release_port_group);
out:
if (fn)
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 11/23] scsi_dh_alua: move optimize_stpg evaluation
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (9 preceding siblings ...)
2016-01-19 8:21 ` [PATCHv4 10/23] revert commit a8e5a2d593cb ("[SCSI] scsi_dh_alua: ALUA handler attach should succeed while TPG is transitioning") Hannes Reinecke
@ 2016-01-19 8:21 ` Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 12/23] scsi_dh_alua: remove 'rel_port' from alua_dh_data structure Hannes Reinecke
` (12 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:21 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke, Hannes Reinecke
When the optimize_stpg module option is set we should just set it
once during port_group allocation. Doing so allows us to override
it later with device specific settings.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.com>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 560924b..10287ac 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -64,6 +64,10 @@
#define ALUA_OPTIMIZE_STPG 1
#define ALUA_RTPG_EXT_HDR_UNSUPP 2
+static uint optimize_stpg;
+module_param(optimize_stpg, uint, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(optimize_stpg, "Allow use of a non-optimized path, rather than sending a STPG, when implicit TPGS is supported (0=No,1=Yes). Default is 0.");
+
static LIST_HEAD(port_group_list);
static DEFINE_SPINLOCK(port_group_lock);
@@ -219,6 +223,8 @@ struct alua_port_group *alua_alloc_pg(struct scsi_device *sdev,
pg->group_id = group_id;
pg->tpgs = tpgs;
pg->state = TPGS_STATE_OPTIMIZED;
+ if (optimize_stpg)
+ pg->flags |= ALUA_OPTIMIZE_STPG;
kref_init(&pg->kref);
spin_lock(&port_group_lock);
@@ -682,10 +688,6 @@ static int alua_set_params(struct scsi_device *sdev, const char *params)
return result;
}
-static uint optimize_stpg;
-module_param(optimize_stpg, uint, S_IRUGO|S_IWUSR);
-MODULE_PARM_DESC(optimize_stpg, "Allow use of a non-optimized path, rather than sending a STPG, when implicit TPGS is supported (0=No,1=Yes). Default is 0.");
-
/*
* alua_activate - activate a path
* @sdev: device on the path to be activated
@@ -707,9 +709,6 @@ static int alua_activate(struct scsi_device *sdev,
kref_get(&h->pg->kref);
- if (optimize_stpg)
- h->pg->flags |= ALUA_OPTIMIZE_STPG;
-
err = alua_rtpg(sdev, h->pg);
if (err != SCSI_DH_OK) {
kref_put(&h->pg->kref, release_port_group);
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 12/23] scsi_dh_alua: remove 'rel_port' from alua_dh_data structure
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (10 preceding siblings ...)
2016-01-19 8:21 ` [PATCHv4 11/23] scsi_dh_alua: move optimize_stpg evaluation Hannes Reinecke
@ 2016-01-19 8:21 ` Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 13/23] scsi_dh_alua: Use workqueue for RTPG Hannes Reinecke
` (11 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:21 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke, Hannes Reinecke
The 'relative port' field is not used, and might get stale when
the port group changes. So remove the field altogether.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.com>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 10287ac..b73a7ed 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -87,7 +87,6 @@ struct alua_port_group {
struct alua_dh_data {
struct alua_port_group *pg;
int group_id;
- int rel_port;
struct scsi_device *sdev;
activate_complete callback_fn;
void *callback_data;
@@ -325,12 +324,10 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h,
return SCSI_DH_NOMEM;
return SCSI_DH_DEV_UNSUPP;
}
- h->rel_port = rel_port;
-
sdev_printk(KERN_INFO, sdev,
"%s: device %s port group %02x rel port %02x\n",
ALUA_DH_NAME, h->pg->device_id_str,
- h->group_id, h->rel_port);
+ h->group_id, rel_port);
return alua_rtpg(sdev, h->pg);
}
@@ -766,7 +763,6 @@ static int alua_bus_attach(struct scsi_device *sdev)
if (!h)
return -ENOMEM;
h->pg = NULL;
- h->rel_port = -1;
h->sdev = sdev;
err = alua_initialize(sdev, h);
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 13/23] scsi_dh_alua: Use workqueue for RTPG
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (11 preceding siblings ...)
2016-01-19 8:21 ` [PATCHv4 12/23] scsi_dh_alua: remove 'rel_port' from alua_dh_data structure Hannes Reinecke
@ 2016-01-19 8:21 ` Hannes Reinecke
2016-02-02 9:32 ` Christoph Hellwig
2016-01-19 8:21 ` [PATCHv4 14/23] scsi_dh_alua: Allow workqueue to run synchronously Hannes Reinecke
` (10 subsequent siblings)
23 siblings, 1 reply; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:21 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
The current ALUA device_handler has two drawbacks:
- We're sending a 'SET TARGET PORT GROUP' command to every LUN,
disregarding the fact that several LUNs might be in a port group
and will be automatically switched whenever _any_ LUN within
that port group receives the command.
- Whenever a LUN is in 'transitioning' mode we cannot block I/O
to that LUN, instead the controller has to abort the command.
This leads to increased traffic across the wire and heavy load
on the controller during switchover.
With this patch the RTPG handling is moved to a per-portgroup
workqueue. This reduces the number of 'REPORT TARGET PORT GROUP'
and 'SET TARGET PORT GROUPS' sent to the controller as we're sending
them now per port group, and not per device as previously.
It also allows us to block I/O to any LUN / port group found to be
in 'transitioning' ALUA mode, as the workqueue item will be requeued
until the controller moves out of transitioning.
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 300 ++++++++++++++++++++++++-----
1 file changed, 248 insertions(+), 52 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index b73a7ed..5824c8a 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -59,10 +59,15 @@
#define ALUA_RTPG_SIZE 128
#define ALUA_FAILOVER_TIMEOUT 60
#define ALUA_FAILOVER_RETRIES 5
+#define ALUA_RTPG_DELAY_MSECS 5
/* device handler flags */
-#define ALUA_OPTIMIZE_STPG 1
-#define ALUA_RTPG_EXT_HDR_UNSUPP 2
+#define ALUA_OPTIMIZE_STPG 0x01
+#define ALUA_RTPG_EXT_HDR_UNSUPP 0x02
+/* State machine flags */
+#define ALUA_PG_RUN_RTPG 0x10
+#define ALUA_PG_RUN_STPG 0x20
+#define ALUA_PG_RUNNING 0x40
static uint optimize_stpg;
module_param(optimize_stpg, uint, S_IRUGO|S_IWUSR);
@@ -70,6 +75,7 @@ MODULE_PARM_DESC(optimize_stpg, "Allow use of a non-optimized path, rather than
static LIST_HEAD(port_group_list);
static DEFINE_SPINLOCK(port_group_lock);
+static struct workqueue_struct *kaluad_wq;
struct alua_port_group {
struct kref kref;
@@ -82,12 +88,25 @@ struct alua_port_group {
int pref;
unsigned flags; /* used for optimizing STPG */
unsigned char transition_tmo;
+ unsigned long expiry;
+ unsigned long interval;
+ struct delayed_work rtpg_work;
+ spinlock_t lock;
+ struct list_head rtpg_list;
+ struct scsi_device *rtpg_sdev;
};
struct alua_dh_data {
struct alua_port_group *pg;
int group_id;
+ spinlock_t pg_lock;
struct scsi_device *sdev;
+ int init_error;
+ struct mutex init_mutex;
+};
+
+struct alua_queue_data {
+ struct list_head entry;
activate_complete callback_fn;
void *callback_data;
};
@@ -95,14 +114,19 @@ struct alua_dh_data {
#define ALUA_POLICY_SWITCH_CURRENT 0
#define ALUA_POLICY_SWITCH_ALL 1
-static int alua_rtpg(struct scsi_device *, struct alua_port_group *);
-static char print_alua_state(int);
+static void alua_rtpg_work(struct work_struct *work);
+static void alua_rtpg_queue(struct alua_port_group *pg,
+ struct scsi_device *sdev,
+ struct alua_queue_data *qdata);
static void release_port_group(struct kref *kref)
{
struct alua_port_group *pg;
+ synchronize_rcu();
pg = container_of(kref, struct alua_port_group, kref);
+ if (pg->rtpg_sdev)
+ flush_delayed_work(&pg->rtpg_work);
spin_lock(&port_group_lock);
list_del(&pg->node);
spin_unlock(&port_group_lock);
@@ -225,6 +249,10 @@ struct alua_port_group *alua_alloc_pg(struct scsi_device *sdev,
if (optimize_stpg)
pg->flags |= ALUA_OPTIMIZE_STPG;
kref_init(&pg->kref);
+ INIT_DELAYED_WORK(&pg->rtpg_work, alua_rtpg_work);
+ INIT_LIST_HEAD(&pg->rtpg_list);
+ INIT_LIST_HEAD(&pg->node);
+ spin_lock_init(&pg->lock);
spin_lock(&port_group_lock);
tmp_pg = alua_find_get_pg(pg->device_id_str, pg->device_id_len,
@@ -304,6 +332,7 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h,
int tpgs)
{
int rel_port = -1, group_id;
+ struct alua_port_group *pg, *old_pg = NULL;
group_id = scsi_vpd_tpg_id(sdev, &rel_port);
if (group_id < 0) {
@@ -318,18 +347,35 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h,
return SCSI_DH_DEV_UNSUPP;
}
- h->pg = alua_alloc_pg(sdev, group_id, tpgs);
- if (PTR_ERR(h->pg)) {
+ pg = alua_alloc_pg(sdev, group_id, tpgs);
+ if (PTR_ERR(pg)) {
if (PTR_ERR(h->pg) == -ENOMEM)
return SCSI_DH_NOMEM;
return SCSI_DH_DEV_UNSUPP;
}
sdev_printk(KERN_INFO, sdev,
"%s: device %s port group %02x rel port %02x\n",
- ALUA_DH_NAME, h->pg->device_id_str,
- h->group_id, rel_port);
+ ALUA_DH_NAME, pg->device_id_str, group_id, rel_port);
+
+ /* Check for existing port group references */
+ spin_lock(&h->pg_lock);
+ if (h->pg) {
+ old_pg = pg;
+ if (h->pg != pg) {
+ /* port group has changed. Update to new port group */
+ old_pg = h->pg;
+ rcu_assign_pointer(h->pg, pg);
+ }
+ } else {
+ rcu_assign_pointer(h->pg, pg);
+ }
+ alua_rtpg_queue(h->pg, sdev, NULL);
+ spin_unlock(&h->pg_lock);
+
+ if (old_pg)
+ kref_put(&old_pg->kref, release_port_group);
- return alua_rtpg(sdev, h->pg);
+ return SCSI_DH_OK;
}
static char print_alua_state(int state)
@@ -423,14 +469,17 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg)
int len, k, off, valid_states = 0, bufflen = ALUA_RTPG_SIZE;
unsigned char *ucp, *buff;
unsigned err, retval;
- unsigned long expiry, interval = 0;
unsigned int tpg_desc_tbl_off;
unsigned char orig_transition_tmo;
- if (!pg->transition_tmo)
- expiry = round_jiffies_up(jiffies + ALUA_FAILOVER_TIMEOUT * HZ);
- else
- expiry = round_jiffies_up(jiffies + pg->transition_tmo * HZ);
+ if (!pg->expiry) {
+ unsigned long transition_tmo = ALUA_FAILOVER_TIMEOUT * HZ;
+
+ if (pg->transition_tmo)
+ transition_tmo = pg->transition_tmo * HZ;
+
+ pg->expiry = round_jiffies_up(jiffies + transition_tmo);
+ }
buff = kzalloc(bufflen, GFP_KERNEL);
if (!buff)
@@ -473,16 +522,18 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg)
err = SCSI_DH_RETRY;
else if (sense_hdr.sense_key == UNIT_ATTENTION)
err = SCSI_DH_RETRY;
- if (err == SCSI_DH_RETRY && time_before(jiffies, expiry)) {
+ if (err == SCSI_DH_RETRY &&
+ pg->expiry != 0 && time_before(jiffies, pg->expiry)) {
sdev_printk(KERN_ERR, sdev, "%s: rtpg retry\n",
ALUA_DH_NAME);
scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr);
- goto retry;
+ return err;
}
sdev_printk(KERN_ERR, sdev, "%s: rtpg failed\n",
ALUA_DH_NAME);
scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr);
kfree(buff);
+ pg->expiry = 0;
return SCSI_DH_IO;
}
@@ -497,6 +548,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg)
sdev_printk(KERN_WARNING, sdev,
"%s: kmalloc buffer failed\n",__func__);
/* Temporary failure, bypass */
+ pg->expiry = 0;
return SCSI_DH_DEV_TEMP_BUSY;
}
goto retry;
@@ -512,7 +564,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg)
sdev_printk(KERN_INFO, sdev,
"%s: transition timeout set to %d seconds\n",
ALUA_DH_NAME, pg->transition_tmo);
- expiry = jiffies + pg->transition_tmo * HZ;
+ pg->expiry = jiffies + pg->transition_tmo * HZ;
}
if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR)
@@ -546,23 +598,26 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg)
switch (pg->state) {
case TPGS_STATE_TRANSITIONING:
- if (time_before(jiffies, expiry)) {
+ if (time_before(jiffies, pg->expiry)) {
/* State transition, retry */
- interval += 2000;
- msleep(interval);
- goto retry;
+ pg->interval = 2;
+ err = SCSI_DH_RETRY;
+ } else {
+ /* Transitioning time exceeded, set port to standby */
+ err = SCSI_DH_IO;
+ pg->state = TPGS_STATE_STANDBY;
+ pg->expiry = 0;
}
- /* Transitioning time exceeded, set port to standby */
- err = SCSI_DH_RETRY;
- pg->state = TPGS_STATE_STANDBY;
break;
case TPGS_STATE_OFFLINE:
/* Path unusable */
err = SCSI_DH_DEV_OFFLINED;
+ pg->expiry = 0;
break;
default:
/* Useable path if active */
err = SCSI_DH_OK;
+ pg->expiry = 0;
break;
}
kfree(buff);
@@ -631,6 +686,106 @@ static unsigned alua_stpg(struct scsi_device *sdev, struct alua_port_group *pg)
return SCSI_DH_RETRY;
}
+static void alua_rtpg_work(struct work_struct *work)
+{
+ struct alua_port_group *pg =
+ container_of(work, struct alua_port_group, rtpg_work.work);
+ struct scsi_device *sdev;
+ LIST_HEAD(qdata_list);
+ int err = SCSI_DH_OK;
+ struct alua_queue_data *qdata, *tmp;
+ unsigned long flags;
+
+ spin_lock_irqsave(&pg->lock, flags);
+ sdev = pg->rtpg_sdev;
+ if (!sdev) {
+ WARN_ON(pg->flags & ALUA_PG_RUN_RTPG ||
+ pg->flags & ALUA_PG_RUN_STPG);
+ spin_unlock_irqrestore(&pg->lock, flags);
+ return;
+ }
+ pg->flags |= ALUA_PG_RUNNING;
+ if (pg->flags & ALUA_PG_RUN_RTPG) {
+ spin_unlock_irqrestore(&pg->lock, flags);
+ err = alua_rtpg(sdev, pg);
+ spin_lock_irqsave(&pg->lock, flags);
+ if (err == SCSI_DH_RETRY) {
+ pg->flags &= ~ALUA_PG_RUNNING;
+ spin_unlock_irqrestore(&pg->lock, flags);
+ queue_delayed_work(kaluad_wq, &pg->rtpg_work,
+ pg->interval * HZ);
+ return;
+ }
+ pg->flags &= ~ALUA_PG_RUN_RTPG;
+ if (err != SCSI_DH_OK)
+ pg->flags &= ~ALUA_PG_RUN_STPG;
+ }
+ if (pg->flags & ALUA_PG_RUN_STPG) {
+ spin_unlock_irqrestore(&pg->lock, flags);
+ err = alua_stpg(sdev, pg);
+ spin_lock_irqsave(&pg->lock, flags);
+ pg->flags &= ~ALUA_PG_RUN_STPG;
+ if (err == SCSI_DH_RETRY) {
+ pg->flags |= ALUA_PG_RUN_RTPG;
+ pg->interval = 0;
+ pg->flags &= ~ALUA_PG_RUNNING;
+ spin_unlock_irqrestore(&pg->lock, flags);
+ queue_delayed_work(kaluad_wq, &pg->rtpg_work,
+ pg->interval * HZ);
+ return;
+ }
+ }
+
+ list_splice_init(&pg->rtpg_list, &qdata_list);
+ pg->rtpg_sdev = NULL;
+ spin_unlock_irqrestore(&pg->lock, flags);
+
+ list_for_each_entry_safe(qdata, tmp, &qdata_list, entry) {
+ list_del(&qdata->entry);
+ if (qdata->callback_fn)
+ qdata->callback_fn(qdata->callback_data, err);
+ kfree(qdata);
+ }
+ spin_lock_irqsave(&pg->lock, flags);
+ pg->flags &= ~ALUA_PG_RUNNING;
+ spin_unlock_irqrestore(&pg->lock, flags);
+ scsi_device_put(sdev);
+ kref_put(&pg->kref, release_port_group);
+}
+
+static void alua_rtpg_queue(struct alua_port_group *pg,
+ struct scsi_device *sdev,
+ struct alua_queue_data *qdata)
+{
+ int start_queue = 0;
+ unsigned long flags;
+
+ if (!pg)
+ return;
+
+ spin_lock_irqsave(&pg->lock, flags);
+ if (qdata) {
+ list_add_tail(&qdata->entry, &pg->rtpg_list);
+ pg->flags |= ALUA_PG_RUN_STPG;
+ }
+ if (pg->rtpg_sdev == NULL) {
+ pg->interval = 0;
+ pg->flags |= ALUA_PG_RUN_RTPG;
+ kref_get(&pg->kref);
+ pg->rtpg_sdev = sdev;
+ scsi_device_get(sdev);
+ start_queue = 1;
+ }
+ spin_unlock_irqrestore(&pg->lock, flags);
+
+ if (start_queue &&
+ !queue_delayed_work(kaluad_wq, &pg->rtpg_work,
+ msecs_to_jiffies(ALUA_RTPG_DELAY_MSECS))) {
+ scsi_device_put(sdev);
+ kref_put(&pg->kref, release_port_group);
+ }
+}
+
/*
* alua_initialize - Initialize ALUA state
* @sdev: the device to be initialized
@@ -642,10 +797,12 @@ static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h)
{
int err = SCSI_DH_DEV_UNSUPP, tpgs;
+ mutex_lock(&h->init_mutex);
tpgs = alua_check_tpgs(sdev);
if (tpgs != TPGS_MODE_NONE)
err = alua_check_vpd(sdev, h, tpgs);
-
+ h->init_error = err;
+ mutex_unlock(&h->init_mutex);
return err;
}
/*
@@ -660,10 +817,11 @@ static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h)
static int alua_set_params(struct scsi_device *sdev, const char *params)
{
struct alua_dh_data *h = sdev->handler_data;
- struct alua_port_group *pg = NULL;
+ struct alua_port_group __rcu *pg = NULL;
unsigned int optimize = 0, argc;
const char *p = params;
int result = SCSI_DH_OK;
+ unsigned long flags;
if ((sscanf(params, "%u", &argc) != 1) || (argc != 1))
return -EINVAL;
@@ -673,14 +831,19 @@ static int alua_set_params(struct scsi_device *sdev, const char *params)
if ((sscanf(p, "%u", &optimize) != 1) || (optimize > 1))
return -EINVAL;
- pg = h->pg;
- if (!pg)
+ rcu_read_lock();
+ pg = rcu_dereference(h->pg);
+ if (!pg) {
+ rcu_read_unlock();
return -ENXIO;
-
+ }
+ spin_lock_irqsave(&pg->lock, flags);
if (optimize)
pg->flags |= ALUA_OPTIMIZE_STPG;
else
pg->flags |= ~ALUA_OPTIMIZE_STPG;
+ spin_unlock_irqrestore(&pg->lock, flags);
+ rcu_read_unlock();
return result;
}
@@ -700,21 +863,33 @@ static int alua_activate(struct scsi_device *sdev,
{
struct alua_dh_data *h = sdev->handler_data;
int err = SCSI_DH_OK;
+ struct alua_queue_data *qdata;
+ struct alua_port_group __rcu *pg;
- if (!h->pg)
+ qdata = kzalloc(sizeof(*qdata), GFP_KERNEL);
+ if (!qdata) {
+ err = SCSI_DH_RES_TEMP_UNAVAIL;
goto out;
-
- kref_get(&h->pg->kref);
-
- err = alua_rtpg(sdev, h->pg);
- if (err != SCSI_DH_OK) {
- kref_put(&h->pg->kref, release_port_group);
+ }
+ qdata->callback_fn = fn;
+ qdata->callback_data = data;
+
+ mutex_lock(&h->init_mutex);
+ rcu_read_lock();
+ pg = rcu_dereference(h->pg);
+ if (!pg || !kref_get_unless_zero(&pg->kref)) {
+ rcu_read_unlock();
+ kfree(qdata);
+ err = h->init_error;
+ mutex_unlock(&h->init_mutex);
goto out;
}
- err = alua_stpg(sdev, h->pg);
- if (err == SCSI_DH_RETRY)
- err = alua_rtpg(sdev, h->pg);
- kref_put(&h->pg->kref, release_port_group);
+ mutex_unlock(&h->init_mutex);
+ fn = NULL;
+ rcu_read_unlock();
+
+ alua_rtpg_queue(pg, sdev, qdata);
+ kref_put(&pg->kref, release_port_group);
out:
if (fn)
fn(data, err);
@@ -730,14 +905,19 @@ out:
static int alua_prep_fn(struct scsi_device *sdev, struct request *req)
{
struct alua_dh_data *h = sdev->handler_data;
- int state;
+ struct alua_port_group __rcu *pg;
+ int state = TPGS_STATE_OPTIMIZED;
int ret = BLKPREP_OK;
- if (!h->pg)
- return ret;
- kref_get(&h->pg->kref);
- state = h->pg->state;
- kref_put(&h->pg->kref, release_port_group);
+ rcu_read_lock();
+ pg = rcu_dereference(h->pg);
+ if (pg) {
+ state = pg->state;
+ /* Defer I/O while rtpg_work is active */
+ if (pg->rtpg_sdev)
+ state = TPGS_STATE_TRANSITIONING;
+ }
+ rcu_read_unlock();
if (state == TPGS_STATE_TRANSITIONING)
ret = BLKPREP_DEFER;
else if (state != TPGS_STATE_OPTIMIZED &&
@@ -762,9 +942,12 @@ static int alua_bus_attach(struct scsi_device *sdev)
h = kzalloc(sizeof(*h) , GFP_KERNEL);
if (!h)
return -ENOMEM;
- h->pg = NULL;
+ spin_lock_init(&h->pg_lock);
+ rcu_assign_pointer(h->pg, NULL);
+ h->init_error = SCSI_DH_OK;
h->sdev = sdev;
+ mutex_init(&h->init_mutex);
err = alua_initialize(sdev, h);
if (err == SCSI_DH_NOMEM)
ret = -ENOMEM;
@@ -785,11 +968,16 @@ failed:
static void alua_bus_detach(struct scsi_device *sdev)
{
struct alua_dh_data *h = sdev->handler_data;
+ struct alua_port_group *pg;
+
+ spin_lock(&h->pg_lock);
+ pg = h->pg;
+ rcu_assign_pointer(h->pg, NULL);
+ h->sdev = NULL;
+ spin_unlock(&h->pg_lock);
+ if (pg)
+ kref_put(&pg->kref, release_port_group);
- if (h->pg) {
- kref_put(&h->pg->kref, release_port_group);
- h->pg = NULL;
- }
sdev->handler_data = NULL;
kfree(h);
}
@@ -809,16 +997,24 @@ static int __init alua_init(void)
{
int r;
+ kaluad_wq = alloc_workqueue("kaluad", WQ_MEM_RECLAIM, 0);
+ if (!kaluad_wq) {
+ /* Temporary failure, bypass */
+ return SCSI_DH_DEV_TEMP_BUSY;
+ }
r = scsi_register_device_handler(&alua_dh);
- if (r != 0)
+ if (r != 0) {
printk(KERN_ERR "%s: Failed to register scsi device handler",
ALUA_DH_NAME);
+ destroy_workqueue(kaluad_wq);
+ }
return r;
}
static void __exit alua_exit(void)
{
scsi_unregister_device_handler(&alua_dh);
+ destroy_workqueue(kaluad_wq);
}
module_init(alua_init);
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* Re: [PATCHv4 13/23] scsi_dh_alua: Use workqueue for RTPG
2016-01-19 8:21 ` [PATCHv4 13/23] scsi_dh_alua: Use workqueue for RTPG Hannes Reinecke
@ 2016-02-02 9:32 ` Christoph Hellwig
0 siblings, 0 replies; 28+ messages in thread
From: Christoph Hellwig @ 2016-02-02 9:32 UTC (permalink / raw)
To: Hannes Reinecke
Cc: Martin K. Petersen, James Bottomley, Christoph Hellwig,
Ewan Milne, Bart van Assche, linux-scsi
> static void release_port_group(struct kref *kref)
> {
> struct alua_port_group *pg;
>
> + synchronize_rcu();
> pg = container_of(kref, struct alua_port_group, kref);
> + if (pg->rtpg_sdev)
> + flush_delayed_work(&pg->rtpg_work);
> spin_lock(&port_group_lock);
> list_del(&pg->node);
> spin_unlock(&port_group_lock);
I don't think this is correct - we need a grace period after the
list_del to prevent new lookups. I suspect the right thing to do here
is to simply use kfree_rcu for the pg. This also avoids waiting for
whole grace periods for each deleted port_group, which might be rather
expensive.
> + /* Check for existing port group references */
> + spin_lock(&h->pg_lock);
> + if (h->pg) {
> + old_pg = pg;
> + if (h->pg != pg) {
> + /* port group has changed. Update to new port group */
> + old_pg = h->pg;
> + rcu_assign_pointer(h->pg, pg);
> + }
> + } else {
> + rcu_assign_pointer(h->pg, pg);
> + }
This looks confusing - pg is the structure we just allocated, so why
do we assign it to old_pg? It seems like the above could be written
similar and more clear as:
olg_pg = h->pg;
if (pg != old_pg)
rcu_assign_pointer(h->pg, pg);
> + if (!sdev) {
> + WARN_ON(pg->flags & ALUA_PG_RUN_RTPG ||
> + pg->flags & ALUA_PG_RUN_STPG);
Please use two separate WARN_ONs here to know which one triggered from
the line in the kernel log.
^ permalink raw reply [flat|nested] 28+ messages in thread
* [PATCHv4 14/23] scsi_dh_alua: Allow workqueue to run synchronously
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (12 preceding siblings ...)
2016-01-19 8:21 ` [PATCHv4 13/23] scsi_dh_alua: Use workqueue for RTPG Hannes Reinecke
@ 2016-01-19 8:21 ` Hannes Reinecke
2016-01-19 8:21 ` [PATCHv4 15/23] scsi_dh_alua: Add new blacklist flag 'BLIST_SYNC_ALUA' Hannes Reinecke
` (9 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:21 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
Some arrays may only capable of handling one STPG at a time,
so this patch adds a singlethreaded workqueue for STPGs to be
submitted synchronously.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 21 ++++++++++++++++++---
1 file changed, 18 insertions(+), 3 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 5824c8a..4a3b0e7 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -64,6 +64,7 @@
/* device handler flags */
#define ALUA_OPTIMIZE_STPG 0x01
#define ALUA_RTPG_EXT_HDR_UNSUPP 0x02
+#define ALUA_SYNC_STPG 0x04
/* State machine flags */
#define ALUA_PG_RUN_RTPG 0x10
#define ALUA_PG_RUN_STPG 0x20
@@ -76,6 +77,7 @@ MODULE_PARM_DESC(optimize_stpg, "Allow use of a non-optimized path, rather than
static LIST_HEAD(port_group_list);
static DEFINE_SPINLOCK(port_group_lock);
static struct workqueue_struct *kaluad_wq;
+static struct workqueue_struct *kaluad_sync_wq;
struct alua_port_group {
struct kref kref;
@@ -695,6 +697,7 @@ static void alua_rtpg_work(struct work_struct *work)
int err = SCSI_DH_OK;
struct alua_queue_data *qdata, *tmp;
unsigned long flags;
+ struct workqueue_struct *alua_wq = kaluad_wq;
spin_lock_irqsave(&pg->lock, flags);
sdev = pg->rtpg_sdev;
@@ -704,6 +707,8 @@ static void alua_rtpg_work(struct work_struct *work)
spin_unlock_irqrestore(&pg->lock, flags);
return;
}
+ if (pg->flags & ALUA_SYNC_STPG)
+ alua_wq = kaluad_sync_wq;
pg->flags |= ALUA_PG_RUNNING;
if (pg->flags & ALUA_PG_RUN_RTPG) {
spin_unlock_irqrestore(&pg->lock, flags);
@@ -712,7 +717,7 @@ static void alua_rtpg_work(struct work_struct *work)
if (err == SCSI_DH_RETRY) {
pg->flags &= ~ALUA_PG_RUNNING;
spin_unlock_irqrestore(&pg->lock, flags);
- queue_delayed_work(kaluad_wq, &pg->rtpg_work,
+ queue_delayed_work(alua_wq, &pg->rtpg_work,
pg->interval * HZ);
return;
}
@@ -730,7 +735,7 @@ static void alua_rtpg_work(struct work_struct *work)
pg->interval = 0;
pg->flags &= ~ALUA_PG_RUNNING;
spin_unlock_irqrestore(&pg->lock, flags);
- queue_delayed_work(kaluad_wq, &pg->rtpg_work,
+ queue_delayed_work(alua_wq, &pg->rtpg_work,
pg->interval * HZ);
return;
}
@@ -759,6 +764,7 @@ static void alua_rtpg_queue(struct alua_port_group *pg,
{
int start_queue = 0;
unsigned long flags;
+ struct workqueue_struct *alua_wq = kaluad_wq;
if (!pg)
return;
@@ -776,10 +782,12 @@ static void alua_rtpg_queue(struct alua_port_group *pg,
scsi_device_get(sdev);
start_queue = 1;
}
+ if (pg->flags & ALUA_SYNC_STPG)
+ alua_wq = kaluad_sync_wq;
spin_unlock_irqrestore(&pg->lock, flags);
if (start_queue &&
- !queue_delayed_work(kaluad_wq, &pg->rtpg_work,
+ !queue_delayed_work(alua_wq, &pg->rtpg_work,
msecs_to_jiffies(ALUA_RTPG_DELAY_MSECS))) {
scsi_device_put(sdev);
kref_put(&pg->kref, release_port_group);
@@ -1002,10 +1010,16 @@ static int __init alua_init(void)
/* Temporary failure, bypass */
return SCSI_DH_DEV_TEMP_BUSY;
}
+ kaluad_sync_wq = create_workqueue("kaluad_sync");
+ if (!kaluad_sync_wq) {
+ destroy_workqueue(kaluad_wq);
+ return SCSI_DH_DEV_TEMP_BUSY;
+ }
r = scsi_register_device_handler(&alua_dh);
if (r != 0) {
printk(KERN_ERR "%s: Failed to register scsi device handler",
ALUA_DH_NAME);
+ destroy_workqueue(kaluad_sync_wq);
destroy_workqueue(kaluad_wq);
}
return r;
@@ -1014,6 +1028,7 @@ static int __init alua_init(void)
static void __exit alua_exit(void)
{
scsi_unregister_device_handler(&alua_dh);
+ destroy_workqueue(kaluad_sync_wq);
destroy_workqueue(kaluad_wq);
}
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 15/23] scsi_dh_alua: Add new blacklist flag 'BLIST_SYNC_ALUA'
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (13 preceding siblings ...)
2016-01-19 8:21 ` [PATCHv4 14/23] scsi_dh_alua: Allow workqueue to run synchronously Hannes Reinecke
@ 2016-01-19 8:21 ` Hannes Reinecke
2016-02-02 9:32 ` Christoph Hellwig
2016-01-19 8:22 ` [PATCHv4 16/23] scsi_dh_alua: Recheck state on unit attention Hannes Reinecke
` (8 subsequent siblings)
23 siblings, 1 reply; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:21 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke, Hannes Reinecke
Add a new blacklist flag BLIST_SYNC_ALUA to instruct the
alua device handler to use synchronous command submission
for ALUA commands.
Signed-off-by: Hannes Reinecke <hare@suse.com>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 2 ++
drivers/scsi/scsi_devinfo.c | 2 ++
drivers/scsi/scsi_scan.c | 3 +++
include/scsi/scsi_device.h | 1 +
include/scsi/scsi_devinfo.h | 1 +
5 files changed, 9 insertions(+)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 4a3b0e7..57dd007 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -371,6 +371,8 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h,
} else {
rcu_assign_pointer(h->pg, pg);
}
+ if (sdev->synchronous_alua)
+ pg->flags |= ALUA_SYNC_STPG;
alua_rtpg_queue(h->pg, sdev, NULL);
spin_unlock(&h->pg_lock);
diff --git a/drivers/scsi/scsi_devinfo.c b/drivers/scsi/scsi_devinfo.c
index 47b9d13..b4ef0c6 100644
--- a/drivers/scsi/scsi_devinfo.c
+++ b/drivers/scsi/scsi_devinfo.c
@@ -218,6 +218,8 @@ static struct {
{"NAKAMICH", "MJ-5.16S", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
{"NEC", "PD-1 ODX654P", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
{"NEC", "iStorage", NULL, BLIST_REPORTLUN2},
+ {"NETAPP", "LUN C-Mode", NULL, BLIST_SYNC_ALUA},
+ {"NETAPP", "INF-01-00", NULL, BLIST_SYNC_ALUA},
{"NRC", "MBR-7", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
{"NRC", "MBR-7.4", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
{"PIONEER", "CD-ROM DRM-600", NULL, BLIST_FORCELUN | BLIST_SINGLELUN},
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index a1c195d..af60709 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -959,6 +959,9 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
if (*bflags & BLIST_NO_DIF)
sdev->no_dif = 1;
+ if (*bflags & BLIST_SYNC_ALUA)
+ sdev->synchronous_alua = 1;
+
sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT;
if (*bflags & BLIST_TRY_VPD_PAGES)
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index f63a167..13339cd 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -176,6 +176,7 @@ struct scsi_device {
unsigned no_dif:1; /* T10 PI (DIF) should be disabled */
unsigned broken_fua:1; /* Don't set FUA bit */
unsigned lun_in_cdb:1; /* Store LUN bits in CDB[1] */
+ unsigned synchronous_alua:1; /* Synchronous ALUA commands */
atomic_t disk_events_disable_depth; /* disable depth for disk events */
diff --git a/include/scsi/scsi_devinfo.h b/include/scsi/scsi_devinfo.h
index 96e3f56..9f750cb 100644
--- a/include/scsi/scsi_devinfo.h
+++ b/include/scsi/scsi_devinfo.h
@@ -37,5 +37,6 @@
#define BLIST_TRY_VPD_PAGES 0x10000000 /* Attempt to read VPD pages */
#define BLIST_NO_RSOC 0x20000000 /* don't try to issue RSOC */
#define BLIST_MAX_1024 0x40000000 /* maximum 1024 sector cdb length */
+#define BLIST_SYNC_ALUA 0x80000000 /* Synchronous ALUA commands */
#endif
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 16/23] scsi_dh_alua: Recheck state on unit attention
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (14 preceding siblings ...)
2016-01-19 8:21 ` [PATCHv4 15/23] scsi_dh_alua: Add new blacklist flag 'BLIST_SYNC_ALUA' Hannes Reinecke
@ 2016-01-19 8:22 ` Hannes Reinecke
2016-01-19 8:22 ` [PATCHv4 17/23] scsi_dh_alua: update all port states Hannes Reinecke
` (7 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:22 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke, Hannes Reinecke
When we receive a unit attention code of 'ALUA state changed'
we should recheck the state, as it might be due to an implicit
ALUA state transition. This allows us to return NEEDS_RETRY
instead of ADD_TO_MLQUEUE, allowing to terminate the retries
after a certain time.
At the same time a workqueue item might already be queued, which
should be started immediately to avoid any delays.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.com>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 57 ++++++++++++++++++++++++------
1 file changed, 46 insertions(+), 11 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 57dd007..0464be9 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -119,7 +119,8 @@ struct alua_queue_data {
static void alua_rtpg_work(struct work_struct *work);
static void alua_rtpg_queue(struct alua_port_group *pg,
struct scsi_device *sdev,
- struct alua_queue_data *qdata);
+ struct alua_queue_data *qdata, bool force);
+static void alua_check(struct scsi_device *sdev, bool force);
static void release_port_group(struct kref *kref)
{
@@ -373,7 +374,7 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h,
}
if (sdev->synchronous_alua)
pg->flags |= ALUA_SYNC_STPG;
- alua_rtpg_queue(h->pg, sdev, NULL);
+ alua_rtpg_queue(h->pg, sdev, NULL, true);
spin_unlock(&h->pg_lock);
if (old_pg)
@@ -409,18 +410,24 @@ static int alua_check_sense(struct scsi_device *sdev,
{
switch (sense_hdr->sense_key) {
case NOT_READY:
- if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0a)
+ if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0a) {
/*
* LUN Not Accessible - ALUA state transition
*/
- return ADD_TO_MLQUEUE;
+ alua_check(sdev, false);
+ return NEEDS_RETRY;
+ }
break;
case UNIT_ATTENTION:
- if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00)
+ if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00) {
/*
- * Power On, Reset, or Bus Device Reset, just retry.
+ * Power On, Reset, or Bus Device Reset.
+ * Might have obscured a state transition,
+ * so schedule a recheck.
*/
+ alua_check(sdev, true);
return ADD_TO_MLQUEUE;
+ }
if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x04)
/*
* Device internal reset
@@ -431,16 +438,20 @@ static int alua_check_sense(struct scsi_device *sdev,
* Mode Parameters Changed
*/
return ADD_TO_MLQUEUE;
- if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x06)
+ if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x06) {
/*
* ALUA state changed
*/
+ alua_check(sdev, true);
return ADD_TO_MLQUEUE;
- if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x07)
+ }
+ if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x07) {
/*
* Implicit ALUA state transition failed
*/
+ alua_check(sdev, true);
return ADD_TO_MLQUEUE;
+ }
if (sense_hdr->asc == 0x3f && sense_hdr->ascq == 0x03)
/*
* Inquiry data has changed
@@ -762,7 +773,7 @@ static void alua_rtpg_work(struct work_struct *work)
static void alua_rtpg_queue(struct alua_port_group *pg,
struct scsi_device *sdev,
- struct alua_queue_data *qdata)
+ struct alua_queue_data *qdata, bool force)
{
int start_queue = 0;
unsigned long flags;
@@ -783,7 +794,9 @@ static void alua_rtpg_queue(struct alua_port_group *pg,
pg->rtpg_sdev = sdev;
scsi_device_get(sdev);
start_queue = 1;
- }
+ } else if (!(pg->flags & ALUA_PG_RUN_RTPG) && force)
+ start_queue = 1;
+
if (pg->flags & ALUA_SYNC_STPG)
alua_wq = kaluad_sync_wq;
spin_unlock_irqrestore(&pg->lock, flags);
@@ -898,7 +911,7 @@ static int alua_activate(struct scsi_device *sdev,
fn = NULL;
rcu_read_unlock();
- alua_rtpg_queue(pg, sdev, qdata);
+ alua_rtpg_queue(pg, sdev, qdata, true);
kref_put(&pg->kref, release_port_group);
out:
if (fn)
@@ -907,6 +920,28 @@ out:
}
/*
+ * alua_check - check path status
+ * @sdev: device on the path to be checked
+ *
+ * Check the device status
+ */
+static void alua_check(struct scsi_device *sdev, bool force)
+{
+ struct alua_dh_data *h = sdev->handler_data;
+ struct alua_port_group *pg;
+
+ rcu_read_lock();
+ pg = rcu_dereference(h->pg);
+ if (!pg || !kref_get_unless_zero(&pg->kref)) {
+ rcu_read_unlock();
+ return;
+ }
+ rcu_read_unlock();
+ alua_rtpg_queue(pg, sdev, NULL, force);
+ kref_put(&pg->kref, release_port_group);
+}
+
+/*
* alua_prep_fn - request callback
*
* Fail I/O to all paths not in state
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 17/23] scsi_dh_alua: update all port states
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (15 preceding siblings ...)
2016-01-19 8:22 ` [PATCHv4 16/23] scsi_dh_alua: Recheck state on unit attention Hannes Reinecke
@ 2016-01-19 8:22 ` Hannes Reinecke
2016-01-19 8:22 ` [PATCHv4 18/23] scsi_dh_alua: Send TEST UNIT READY to poll for transitioning Hannes Reinecke
` (6 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:22 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
When we read in the target port group state we should be
updating all affected port groups, otherwise we risk
running out of sync.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 31 +++++++++++++++++++++---------
1 file changed, 22 insertions(+), 9 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 0464be9..a8273cc 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -481,11 +481,13 @@ static int alua_check_sense(struct scsi_device *sdev,
static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg)
{
struct scsi_sense_hdr sense_hdr;
+ struct alua_port_group *tmp_pg;
int len, k, off, valid_states = 0, bufflen = ALUA_RTPG_SIZE;
- unsigned char *ucp, *buff;
+ unsigned char *desc, *buff;
unsigned err, retval;
unsigned int tpg_desc_tbl_off;
unsigned char orig_transition_tmo;
+ unsigned long flags;
if (!pg->expiry) {
unsigned long transition_tmo = ALUA_FAILOVER_TIMEOUT * HZ;
@@ -587,16 +589,27 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg)
else
tpg_desc_tbl_off = 4;
- for (k = tpg_desc_tbl_off, ucp = buff + tpg_desc_tbl_off;
+ for (k = tpg_desc_tbl_off, desc = buff + tpg_desc_tbl_off;
k < len;
- k += off, ucp += off) {
-
- if (pg->group_id == get_unaligned_be16(&ucp[2])) {
- pg->state = ucp[0] & 0x0f;
- pg->pref = ucp[0] >> 7;
- valid_states = ucp[1];
+ k += off, desc += off) {
+ u16 group_id = get_unaligned_be16(&desc[2]);
+
+ spin_lock_irqsave(&port_group_lock, flags);
+ list_for_each_entry(tmp_pg, &port_group_list, node) {
+ if (tmp_pg->group_id != group_id)
+ continue;
+ if (tmp_pg->device_id_len != pg->device_id_len)
+ continue;
+ if (strncmp(tmp_pg->device_id_str, pg->device_id_str,
+ tmp_pg->device_id_len))
+ continue;
+ tmp_pg->state = desc[0] & 0x0f;
+ tmp_pg->pref = desc[0] >> 7;
+ if (tmp_pg == pg)
+ valid_states = desc[1];
}
- off = 8 + (ucp[7] * 4);
+ spin_unlock_irqrestore(&port_group_lock, flags);
+ off = 8 + (desc[7] * 4);
}
sdev_printk(KERN_INFO, sdev,
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 18/23] scsi_dh_alua: Send TEST UNIT READY to poll for transitioning
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (16 preceding siblings ...)
2016-01-19 8:22 ` [PATCHv4 17/23] scsi_dh_alua: update all port states Hannes Reinecke
@ 2016-01-19 8:22 ` Hannes Reinecke
2016-01-19 8:22 ` [PATCHv4 19/23] scsi_dh: add 'rescan' callback Hannes Reinecke
` (5 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:22 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
Sending a 'REPORT TARGET PORT GROUP' command is a costly operation,
as the array has to gather information about all ports.
So instead of using RTPG to poll for a status update when a port
is in transitioning we should be sending a TEST UNIT READY, and
wait for the sense code to report success.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Ewan Milne <emilne@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 37 ++++++++++++++++++++++++++++++
1 file changed, 37 insertions(+)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index a8273cc..7f28115 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -471,6 +471,30 @@ static int alua_check_sense(struct scsi_device *sdev,
}
/*
+ * alua_tur - Send a TEST UNIT READY
+ * @sdev: device to which the TEST UNIT READY command should be send
+ *
+ * Send a TEST UNIT READY to @sdev to figure out the device state
+ * Returns SCSI_DH_RETRY if the sense code is NOT READY/ALUA TRANSITIONING,
+ * SCSI_DH_OK if no error occurred, and SCSI_DH_IO otherwise.
+ */
+static int alua_tur(struct scsi_device *sdev)
+{
+ struct scsi_sense_hdr sense_hdr;
+ int retval;
+
+ retval = scsi_test_unit_ready(sdev, ALUA_FAILOVER_TIMEOUT * HZ,
+ ALUA_FAILOVER_RETRIES, &sense_hdr);
+ if (sense_hdr.sense_key == NOT_READY &&
+ sense_hdr.asc == 0x04 && sense_hdr.ascq == 0x0a)
+ return SCSI_DH_RETRY;
+ else if (retval)
+ return SCSI_DH_IO;
+ else
+ return SCSI_DH_OK;
+}
+
+/*
* alua_rtpg - Evaluate REPORT TARGET GROUP STATES
* @sdev: the device to be evaluated.
*
@@ -737,7 +761,20 @@ static void alua_rtpg_work(struct work_struct *work)
alua_wq = kaluad_sync_wq;
pg->flags |= ALUA_PG_RUNNING;
if (pg->flags & ALUA_PG_RUN_RTPG) {
+ int state = pg->state;
+
spin_unlock_irqrestore(&pg->lock, flags);
+ if (state == TPGS_STATE_TRANSITIONING) {
+ if (alua_tur(sdev) == SCSI_DH_RETRY) {
+ spin_lock_irqsave(&pg->lock, flags);
+ pg->flags &= ~ALUA_PG_RUNNING;
+ spin_unlock_irqrestore(&pg->lock, flags);
+ queue_delayed_work(alua_wq, &pg->rtpg_work,
+ pg->interval * HZ);
+ return;
+ }
+ /* Send RTPG on failure or if TUR indicates SUCCESS */
+ }
err = alua_rtpg(sdev, pg);
spin_lock_irqsave(&pg->lock, flags);
if (err == SCSI_DH_RETRY) {
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 19/23] scsi_dh: add 'rescan' callback
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (17 preceding siblings ...)
2016-01-19 8:22 ` [PATCHv4 18/23] scsi_dh_alua: Send TEST UNIT READY to poll for transitioning Hannes Reinecke
@ 2016-01-19 8:22 ` Hannes Reinecke
2016-01-19 8:22 ` [PATCHv4 20/23] scsi: Add 'access_state' attribute Hannes Reinecke
` (4 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:22 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
If a device needs to be rescanned the device_handler might need
to be rechecked, too.
So add a 'rescan' callback to the device handler and call it
upon scsi_rescan_device().
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 8 ++++++++
drivers/scsi/scsi_lib.c | 1 +
drivers/scsi/scsi_scan.c | 8 +++++++-
include/scsi/scsi_dh.h | 1 +
4 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 7f28115..57856d6 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -1025,6 +1025,13 @@ static int alua_prep_fn(struct scsi_device *sdev, struct request *req)
}
+static void alua_rescan(struct scsi_device *sdev)
+{
+ struct alua_dh_data *h = sdev->handler_data;
+
+ alua_initialize(sdev, h);
+}
+
/*
* alua_bus_attach - Attach device handler
* @sdev: device to be attached to
@@ -1085,6 +1092,7 @@ static struct scsi_device_handler alua_dh = {
.prep_fn = alua_prep_fn,
.check_sense = alua_check_sense,
.activate = alua_activate,
+ .rescan = alua_rescan,
.set_params = alua_set_params,
};
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index fa6b2c4..d46193a 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -2699,6 +2699,7 @@ static void scsi_evt_emit(struct scsi_device *sdev, struct scsi_event *evt)
envp[idx++] = "SDEV_MEDIA_CHANGE=1";
break;
case SDEV_EVT_INQUIRY_CHANGE_REPORTED:
+ scsi_rescan_device(&sdev->sdev_gendev);
envp[idx++] = "SDEV_UA=INQUIRY_DATA_HAS_CHANGED";
break;
case SDEV_EVT_CAPACITY_CHANGE_REPORTED:
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index af60709..4d61604 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -43,6 +43,7 @@
#include <scsi/scsi_devinfo.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_transport.h>
+#include <scsi/scsi_dh.h>
#include <scsi/scsi_eh.h>
#include "scsi_priv.h"
@@ -1519,9 +1520,14 @@ EXPORT_SYMBOL(scsi_add_device);
void scsi_rescan_device(struct device *dev)
{
+ struct scsi_device *sdev = to_scsi_device(dev);
+
device_lock(dev);
- scsi_attach_vpd(to_scsi_device(dev));
+ scsi_attach_vpd(sdev);
+
+ if (sdev->handler && sdev->handler->rescan)
+ sdev->handler->rescan(sdev);
if (dev->driver && try_module_get(dev->driver->owner)) {
struct scsi_driver *drv = to_scsi_driver(dev->driver);
diff --git a/include/scsi/scsi_dh.h b/include/scsi/scsi_dh.h
index 7e184c6..c7bba2b 100644
--- a/include/scsi/scsi_dh.h
+++ b/include/scsi/scsi_dh.h
@@ -71,6 +71,7 @@ struct scsi_device_handler {
int (*activate)(struct scsi_device *, activate_complete, void *);
int (*prep_fn)(struct scsi_device *, struct request *);
int (*set_params)(struct scsi_device *, const char *);
+ void (*rescan)(struct scsi_device *);
};
#ifdef CONFIG_SCSI_DH
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 20/23] scsi: Add 'access_state' attribute
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (18 preceding siblings ...)
2016-01-19 8:22 ` [PATCHv4 19/23] scsi_dh: add 'rescan' callback Hannes Reinecke
@ 2016-01-19 8:22 ` Hannes Reinecke
2016-01-19 8:22 ` [PATCHv4 21/23] scsi_dh_alua: use common definitions for ALUA state Hannes Reinecke
` (3 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:22 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
Add an 'access_state' attribute to struct scsi_device to
display the asymmetric LUN access state.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/scsi_scan.c | 1 +
drivers/scsi/scsi_sysfs.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++
include/scsi/scsi_device.h | 1 +
include/scsi/scsi_proto.h | 13 ++++++++++++
4 files changed, 64 insertions(+)
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 4d61604..a7c6862 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -231,6 +231,7 @@ static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
sdev->lun = lun;
sdev->channel = starget->channel;
sdev->sdev_state = SDEV_CREATED;
+ sdev->access_state = SCSI_ACCESS_STATE_UNKNOWN;
INIT_LIST_HEAD(&sdev->siblings);
INIT_LIST_HEAD(&sdev->same_target_siblings);
INIT_LIST_HEAD(&sdev->cmd_list);
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index ef36053..80b4c67 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -81,6 +81,34 @@ const char *scsi_host_state_name(enum scsi_host_state state)
return name;
}
+static const struct {
+ enum scsi_access_state value;
+ char *name;
+} sdev_access_states[] = {
+ { SCSI_ACCESS_STATE_OPTIMAL, "active/optimized" },
+ { SCSI_ACCESS_STATE_ACTIVE, "active/non-optimized" },
+ { SCSI_ACCESS_STATE_STANDBY, "standby" },
+ { SCSI_ACCESS_STATE_UNAVAILABLE, "unavailable" },
+ { SCSI_ACCESS_STATE_LBA, "lba-dependent" },
+ { SCSI_ACCESS_STATE_OFFLINE, "offline" },
+ { SCSI_ACCESS_STATE_TRANSITIONING, "transitioning" },
+ { SCSI_ACCESS_STATE_UNKNOWN, "unknown" },
+};
+
+const char *scsi_access_state_name(enum scsi_access_state state)
+{
+ int i;
+ char *name = NULL;
+
+ for (i = 0; i < ARRAY_SIZE(sdev_access_states); i++) {
+ if (sdev_access_states[i].value == state) {
+ name = sdev_access_states[i].name;
+ break;
+ }
+ }
+ return name;
+}
+
static int check_set(unsigned long long *val, char *src)
{
char *last;
@@ -973,6 +1001,26 @@ sdev_store_dh_state(struct device *dev, struct device_attribute *attr,
static DEVICE_ATTR(dh_state, S_IRUGO | S_IWUSR, sdev_show_dh_state,
sdev_store_dh_state);
+
+static ssize_t
+sdev_show_access_state(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct scsi_device *sdev = to_scsi_device(dev);
+ enum scsi_access_state access_state;
+ bool pref = false;
+
+ if (sdev->access_state & SCSI_ACCESS_STATE_PREFERRED)
+ pref = true;
+
+ access_state = (sdev->access_state & SCSI_ACCESS_STATE_MASK);
+
+ return snprintf(buf, 32, "%s%s\n",
+ scsi_access_state_name(access_state),
+ pref ? " preferred" : "");
+}
+static DEVICE_ATTR(access_state, S_IRUGO, sdev_show_access_state, NULL);
#endif
static ssize_t
@@ -1047,6 +1095,7 @@ static struct attribute *scsi_sdev_attrs[] = {
&dev_attr_wwid.attr,
#ifdef CONFIG_SCSI_DH
&dev_attr_dh_state.attr,
+ &dev_attr_access_state.attr,
#endif
&dev_attr_queue_ramp_up_period.attr,
REF_EVT(media_change),
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 13339cd..a5fc682 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -201,6 +201,7 @@ struct scsi_device {
struct scsi_device_handler *handler;
void *handler_data;
+ enum scsi_access_state access_state;
enum scsi_device_state sdev_state;
unsigned long sdev_data[0];
} __attribute__((aligned(sizeof(unsigned long))));
diff --git a/include/scsi/scsi_proto.h b/include/scsi/scsi_proto.h
index a9fbf1b..80e85e7 100644
--- a/include/scsi/scsi_proto.h
+++ b/include/scsi/scsi_proto.h
@@ -277,5 +277,18 @@ struct scsi_lun {
__u8 scsi_lun[8];
};
+/* SPC asymmetric access states */
+enum scsi_access_state {
+ SCSI_ACCESS_STATE_OPTIMAL = 0,
+ SCSI_ACCESS_STATE_ACTIVE,
+ SCSI_ACCESS_STATE_STANDBY,
+ SCSI_ACCESS_STATE_UNAVAILABLE,
+ SCSI_ACCESS_STATE_LBA,
+ SCSI_ACCESS_STATE_OFFLINE = 0xe,
+ SCSI_ACCESS_STATE_TRANSITIONING = 0xf,
+ SCSI_ACCESS_STATE_UNKNOWN = 0x70,
+};
+#define SCSI_ACCESS_STATE_MASK 0x0f
+#define SCSI_ACCESS_STATE_PREFERRED 0x80
#endif /* _SCSI_PROTO_H_ */
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 21/23] scsi_dh_alua: use common definitions for ALUA state
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (19 preceding siblings ...)
2016-01-19 8:22 ` [PATCHv4 20/23] scsi: Add 'access_state' attribute Hannes Reinecke
@ 2016-01-19 8:22 ` Hannes Reinecke
2016-01-19 8:22 ` [PATCHv4 22/23] scsi_dh_alua: update 'access_state' field Hannes Reinecke
` (2 subsequent siblings)
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:22 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
scsi_proto.h now contains definitions for the ALUA state,
so we don't have to carry them in the device handler.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 62 +++++++++++++-----------------
1 file changed, 27 insertions(+), 35 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 57856d6..df8e06f 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -31,14 +31,6 @@
#define ALUA_DH_NAME "alua"
#define ALUA_DH_VER "1.3"
-#define TPGS_STATE_OPTIMIZED 0x0
-#define TPGS_STATE_NONOPTIMIZED 0x1
-#define TPGS_STATE_STANDBY 0x2
-#define TPGS_STATE_UNAVAILABLE 0x3
-#define TPGS_STATE_LBA_DEPENDENT 0x4
-#define TPGS_STATE_OFFLINE 0xe
-#define TPGS_STATE_TRANSITIONING 0xf
-
#define TPGS_SUPPORT_NONE 0x00
#define TPGS_SUPPORT_OPTIMIZED 0x01
#define TPGS_SUPPORT_NONOPTIMIZED 0x02
@@ -180,7 +172,7 @@ static int submit_stpg(struct scsi_device *sdev, int group_id,
/* Prepare the data buffer */
memset(stpg_data, 0, stpg_len);
- stpg_data[4] = TPGS_STATE_OPTIMIZED & 0x0f;
+ stpg_data[4] = SCSI_ACCESS_STATE_OPTIMAL & 0x0f;
put_unaligned_be16(group_id, &stpg_data[6]);
/* Prepare the command. */
@@ -248,7 +240,7 @@ struct alua_port_group *alua_alloc_pg(struct scsi_device *sdev,
}
pg->group_id = group_id;
pg->tpgs = tpgs;
- pg->state = TPGS_STATE_OPTIMIZED;
+ pg->state = SCSI_ACCESS_STATE_OPTIMAL;
if (optimize_stpg)
pg->flags |= ALUA_OPTIMIZE_STPG;
kref_init(&pg->kref);
@@ -383,22 +375,22 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h,
return SCSI_DH_OK;
}
-static char print_alua_state(int state)
+static char print_alua_state(enum scsi_access_state state)
{
switch (state) {
- case TPGS_STATE_OPTIMIZED:
+ case SCSI_ACCESS_STATE_OPTIMAL:
return 'A';
- case TPGS_STATE_NONOPTIMIZED:
+ case SCSI_ACCESS_STATE_ACTIVE:
return 'N';
- case TPGS_STATE_STANDBY:
+ case SCSI_ACCESS_STATE_STANDBY:
return 'S';
- case TPGS_STATE_UNAVAILABLE:
+ case SCSI_ACCESS_STATE_UNAVAILABLE:
return 'U';
- case TPGS_STATE_LBA_DEPENDENT:
+ case SCSI_ACCESS_STATE_LBA:
return 'L';
- case TPGS_STATE_OFFLINE:
+ case SCSI_ACCESS_STATE_OFFLINE:
return 'O';
- case TPGS_STATE_TRANSITIONING:
+ case SCSI_ACCESS_STATE_TRANSITIONING:
return 'T';
default:
return 'X';
@@ -649,7 +641,7 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg)
valid_states&TPGS_SUPPORT_OPTIMIZED?'A':'a');
switch (pg->state) {
- case TPGS_STATE_TRANSITIONING:
+ case SCSI_ACCESS_STATE_TRANSITIONING:
if (time_before(jiffies, pg->expiry)) {
/* State transition, retry */
pg->interval = 2;
@@ -657,11 +649,11 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg)
} else {
/* Transitioning time exceeded, set port to standby */
err = SCSI_DH_IO;
- pg->state = TPGS_STATE_STANDBY;
+ pg->state = SCSI_ACCESS_STATE_STANDBY;
pg->expiry = 0;
}
break;
- case TPGS_STATE_OFFLINE:
+ case SCSI_ACCESS_STATE_OFFLINE:
/* Path unusable */
err = SCSI_DH_DEV_OFFLINED;
pg->expiry = 0;
@@ -694,21 +686,21 @@ static unsigned alua_stpg(struct scsi_device *sdev, struct alua_port_group *pg)
return SCSI_DH_RETRY;
}
switch (pg->state) {
- case TPGS_STATE_OPTIMIZED:
+ case SCSI_ACCESS_STATE_OPTIMAL:
return SCSI_DH_OK;
- case TPGS_STATE_NONOPTIMIZED:
+ case SCSI_ACCESS_STATE_ACTIVE:
if ((pg->flags & ALUA_OPTIMIZE_STPG) &&
!pg->pref &&
(pg->tpgs & TPGS_MODE_IMPLICIT))
return SCSI_DH_OK;
break;
- case TPGS_STATE_STANDBY:
- case TPGS_STATE_UNAVAILABLE:
+ case SCSI_ACCESS_STATE_STANDBY:
+ case SCSI_ACCESS_STATE_UNAVAILABLE:
break;
- case TPGS_STATE_OFFLINE:
+ case SCSI_ACCESS_STATE_OFFLINE:
return SCSI_DH_IO;
break;
- case TPGS_STATE_TRANSITIONING:
+ case SCSI_ACCESS_STATE_TRANSITIONING:
break;
default:
sdev_printk(KERN_INFO, sdev,
@@ -718,7 +710,7 @@ static unsigned alua_stpg(struct scsi_device *sdev, struct alua_port_group *pg)
break;
}
/* Set state to transitioning */
- pg->state = TPGS_STATE_TRANSITIONING;
+ pg->state = SCSI_ACCESS_STATE_TRANSITIONING;
retval = submit_stpg(sdev, pg->group_id, &sense_hdr);
if (retval) {
@@ -764,7 +756,7 @@ static void alua_rtpg_work(struct work_struct *work)
int state = pg->state;
spin_unlock_irqrestore(&pg->lock, flags);
- if (state == TPGS_STATE_TRANSITIONING) {
+ if (state == SCSI_ACCESS_STATE_TRANSITIONING) {
if (alua_tur(sdev) == SCSI_DH_RETRY) {
spin_lock_irqsave(&pg->lock, flags);
pg->flags &= ~ALUA_PG_RUNNING;
@@ -1001,7 +993,7 @@ static int alua_prep_fn(struct scsi_device *sdev, struct request *req)
{
struct alua_dh_data *h = sdev->handler_data;
struct alua_port_group __rcu *pg;
- int state = TPGS_STATE_OPTIMIZED;
+ enum scsi_access_state state = SCSI_ACCESS_STATE_OPTIMAL;
int ret = BLKPREP_OK;
rcu_read_lock();
@@ -1010,14 +1002,14 @@ static int alua_prep_fn(struct scsi_device *sdev, struct request *req)
state = pg->state;
/* Defer I/O while rtpg_work is active */
if (pg->rtpg_sdev)
- state = TPGS_STATE_TRANSITIONING;
+ state = SCSI_ACCESS_STATE_TRANSITIONING;
}
rcu_read_unlock();
- if (state == TPGS_STATE_TRANSITIONING)
+ if (state == SCSI_ACCESS_STATE_TRANSITIONING)
ret = BLKPREP_DEFER;
- else if (state != TPGS_STATE_OPTIMIZED &&
- state != TPGS_STATE_NONOPTIMIZED &&
- state != TPGS_STATE_LBA_DEPENDENT) {
+ else if (state != SCSI_ACCESS_STATE_OPTIMAL &&
+ state != SCSI_ACCESS_STATE_ACTIVE &&
+ state != SCSI_ACCESS_STATE_LBA) {
ret = BLKPREP_KILL;
req->cmd_flags |= REQ_QUIET;
}
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 22/23] scsi_dh_alua: update 'access_state' field
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (20 preceding siblings ...)
2016-01-19 8:22 ` [PATCHv4 21/23] scsi_dh_alua: use common definitions for ALUA state Hannes Reinecke
@ 2016-01-19 8:22 ` Hannes Reinecke
2016-02-02 18:16 ` Christoph Hellwig
2016-01-19 8:22 ` [PATCHv4 23/23] scsi_dh_alua: Update version to 2.0 Hannes Reinecke
2016-02-02 2:35 ` [PATCHv4 00/23] ALUA device handler update, part II Martin K. Petersen
23 siblings, 1 reply; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:22 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
Track attached SCSI devices and update the 'access_state' field
whenever an ALUA state change has been detected.
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 34 ++++++++++++++++++++++++++++--
1 file changed, 32 insertions(+), 2 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index df8e06f..5352139 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -24,6 +24,7 @@
#include <linux/module.h>
#include <asm/unaligned.h>
#include <scsi/scsi.h>
+#include <scsi/scsi_proto.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_dh.h>
@@ -74,6 +75,7 @@ static struct workqueue_struct *kaluad_sync_wq;
struct alua_port_group {
struct kref kref;
struct list_head node;
+ struct list_head dh_list;
unsigned char device_id_str[256];
int device_id_len;
int group_id;
@@ -91,6 +93,7 @@ struct alua_port_group {
};
struct alua_dh_data {
+ struct list_head node;
struct alua_port_group *pg;
int group_id;
spinlock_t pg_lock;
@@ -247,6 +250,7 @@ struct alua_port_group *alua_alloc_pg(struct scsi_device *sdev,
INIT_DELAYED_WORK(&pg->rtpg_work, alua_rtpg_work);
INIT_LIST_HEAD(&pg->rtpg_list);
INIT_LIST_HEAD(&pg->node);
+ INIT_LIST_HEAD(&pg->dh_list);
spin_lock_init(&pg->lock);
spin_lock(&port_group_lock);
@@ -328,6 +332,8 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h,
{
int rel_port = -1, group_id;
struct alua_port_group *pg, *old_pg = NULL;
+ bool pg_updated;
+ unsigned long flags;
group_id = scsi_vpd_tpg_id(sdev, &rel_port);
if (group_id < 0) {
@@ -359,16 +365,27 @@ static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h,
if (h->pg != pg) {
/* port group has changed. Update to new port group */
old_pg = h->pg;
+ spin_lock_irqsave(&old_pg->lock, flags);
+ list_del_rcu(&h->node);
+ spin_unlock_irqrestore(&old_pg->lock, flags);
rcu_assign_pointer(h->pg, pg);
+ pg_updated = true;
}
} else {
rcu_assign_pointer(h->pg, pg);
+ pg_updated = true;
}
if (sdev->synchronous_alua)
pg->flags |= ALUA_SYNC_STPG;
alua_rtpg_queue(h->pg, sdev, NULL, true);
spin_unlock(&h->pg_lock);
+ if (pg_updated) {
+ spin_lock_irqsave(&pg->lock, flags);
+ list_add_rcu(&h->node, &pg->dh_list);
+ spin_unlock_irqrestore(&pg->lock, flags);
+ }
+
if (old_pg)
kref_put(&old_pg->kref, release_port_group);
@@ -612,6 +629,8 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg)
spin_lock_irqsave(&port_group_lock, flags);
list_for_each_entry(tmp_pg, &port_group_list, node) {
+ struct alua_dh_data *h;
+
if (tmp_pg->group_id != group_id)
continue;
if (tmp_pg->device_id_len != pg->device_id_len)
@@ -621,6 +640,13 @@ static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg)
continue;
tmp_pg->state = desc[0] & 0x0f;
tmp_pg->pref = desc[0] >> 7;
+ rcu_read_lock();
+ list_for_each_entry_rcu(h, &tmp_pg->dh_list, node) {
+ /* h->sdev should always be valid */
+ BUG_ON(!h->sdev);
+ h->sdev->access_state = desc[0];
+ }
+ rcu_read_unlock();
if (tmp_pg == pg)
valid_states = desc[1];
}
@@ -1040,6 +1066,7 @@ static int alua_bus_attach(struct scsi_device *sdev)
rcu_assign_pointer(h->pg, NULL);
h->init_error = SCSI_DH_OK;
h->sdev = sdev;
+ INIT_LIST_HEAD(&h->node);
mutex_init(&h->init_mutex);
err = alua_initialize(sdev, h);
@@ -1069,9 +1096,12 @@ static void alua_bus_detach(struct scsi_device *sdev)
rcu_assign_pointer(h->pg, NULL);
h->sdev = NULL;
spin_unlock(&h->pg_lock);
- if (pg)
+ if (pg) {
+ spin_lock(&pg->lock);
+ list_del_rcu(&h->node);
+ spin_unlock(&pg->lock);
kref_put(&pg->kref, release_port_group);
-
+ }
sdev->handler_data = NULL;
kfree(h);
}
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* [PATCHv4 23/23] scsi_dh_alua: Update version to 2.0
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (21 preceding siblings ...)
2016-01-19 8:22 ` [PATCHv4 22/23] scsi_dh_alua: update 'access_state' field Hannes Reinecke
@ 2016-01-19 8:22 ` Hannes Reinecke
2016-02-02 2:35 ` [PATCHv4 00/23] ALUA device handler update, part II Martin K. Petersen
23 siblings, 0 replies; 28+ messages in thread
From: Hannes Reinecke @ 2016-01-19 8:22 UTC (permalink / raw)
To: Martin K. Petersen
Cc: James Bottomley, Christoph Hellwig, Ewan Milne, Bart van Assche,
linux-scsi, Hannes Reinecke
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c
index 5352139..52f1d25 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -30,7 +30,7 @@
#include <scsi/scsi_dh.h>
#define ALUA_DH_NAME "alua"
-#define ALUA_DH_VER "1.3"
+#define ALUA_DH_VER "2.0"
#define TPGS_SUPPORT_NONE 0x00
#define TPGS_SUPPORT_OPTIMIZED 0x01
--
1.8.5.6
^ permalink raw reply related [flat|nested] 28+ messages in thread* Re: [PATCHv4 00/23] ALUA device handler update, part II
2016-01-19 8:21 [PATCHv4 00/23] ALUA device handler update, part II Hannes Reinecke
` (22 preceding siblings ...)
2016-01-19 8:22 ` [PATCHv4 23/23] scsi_dh_alua: Update version to 2.0 Hannes Reinecke
@ 2016-02-02 2:35 ` Martin K. Petersen
23 siblings, 0 replies; 28+ messages in thread
From: Martin K. Petersen @ 2016-02-02 2:35 UTC (permalink / raw)
To: Hannes Reinecke
Cc: Martin K. Petersen, James Bottomley, Christoph Hellwig,
Ewan Milne, Bart van Assche, linux-scsi
>>>>> "Hannes" == Hannes Reinecke <hare@suse.de> writes:
Hannes> as promised here is now the second part of my ALUA device
Hannes> handler update. This contains a major rework of the ALUA device
Hannes> handler as execution is moved onto a workqueue. This has the
Hannes> advantage that we avoid having to do multiple calls to the same
Hannes> LUN (as happens frequently when failing over a LUN with several
Hannes> paths) and finally retries are handled correctly.
I would really like to get this series merged but I need reviews for:
[PATCHv4 13/23] scsi_dh_alua: Use workqueue for RTPG
https://patchwork.kernel.org/patch/8058991/
[PATCHv4 15/23] scsi_dh_alua: Add new blacklist flag 'BLIST_SYNC_ALUA'
https://patchwork.kernel.org/patch/8058951/
[PATCHv4 22/23] scsi_dh_alua: update 'access_state' field
https://patchwork.kernel.org/patch/8059021/
--
Martin K. Petersen Oracle Linux Engineering
^ permalink raw reply [flat|nested] 28+ messages in thread