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scsi_dh_alua: Use separate alua_port_group structure

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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>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Hannes Reinecke 2016-02-19 09:17:04 +01:00 committed by Martin K. Petersen
parent c49c83458f
commit 43394c67f8
2 changed files with 130 additions and 54 deletions
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183
drivers/scsi/device_handler/scsi_dh_alua.c
View File

@ -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
@ -141,6 +162,35 @@ static int submit_stpg(struct scsi_device *sdev, int group_id,
ALUA_FAILOVER_RETRIES, NULL, req_flags);
}
/*
* 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:
@ -506,10 +555,10 @@ 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;
}
retval = submit_stpg(sdev, h->group_id, &sense_hdr);
retval = submit_stpg(sdev, pg->group_id, &sense_hdr);
if (retval) {
if (!scsi_sense_valid(&sense_hdr)) {
@ -519,7 +568,7 @@ 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);
}
@ -537,20 +586,24 @@ 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;
}
@ -566,6 +619,7 @@ 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;
@ -578,10 +632,14 @@ 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;
}
@ -606,16 +664,23 @@ 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;
if (optimize_stpg)
h->flags |= ALUA_OPTIMIZE_STPG;
kref_get(&h->pg->kref);
err = alua_stpg(sdev, h);
if (optimize_stpg)
h->pg->flags |= ALUA_OPTIMIZE_STPG;
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);
@ -631,13 +696,19 @@ 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;
}
@ -652,18 +723,18 @@ 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;
@ -671,7 +742,7 @@ static int alua_bus_attach(struct scsi_device *sdev)
return 0;
failed:
kfree(h);
return -EINVAL;
return ret;
}
/*
@ -682,6 +753,10 @@ 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);
}

1
include/scsi/scsi_dh.h
View File

@ -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,
};