The port group needs to be a separate structure as several
LUNs might belong to the same group.
Reviewed-by: Ewan Milne <emi...@redhat.com>
Signed-off-by: Hannes Reinecke <h...@suse.de>
---
drivers/scsi/device_handler/scsi_dh_alua.c | 221 ++++++++++++++++++++---------
include/scsi/scsi_dh.h | 1 +
2 files changed, 151 insertions(+), 71 deletions(-)
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c
b/drivers/scsi/device_handler/scsi_dh_alua.c
index 063c03a..f3191f7 100644
--- a/drivers/scsi/device_handler/scsi_dh_alua.c
+++ b/drivers/scsi/device_handler/scsi_dh_alua.c
@@ -64,9 +64,13 @@
#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;
@@ -75,6 +79,12 @@ struct alua_dh_data {
unsigned char *buff;
int bufflen;
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;
@@ -85,21 +95,34 @@ struct alua_dh_data {
static char print_alua_state(int);
-static int realloc_buffer(struct alua_dh_data *h, unsigned len)
+static int realloc_buffer(struct alua_port_group *pg, unsigned len)
{
- if (h->buff && h->buff != h->inq)
- kfree(h->buff);
+ if (pg->buff && pg->buff != pg->inq)
+ kfree(pg->buff);
- h->buff = kmalloc(len, GFP_NOIO);
- if (!h->buff) {
- h->buff = h->inq;
- h->bufflen = ALUA_INQUIRY_SIZE;
+ pg->buff = kmalloc(len, GFP_NOIO);
+ if (!pg->buff) {
+ pg->buff = pg->inq;
+ pg->bufflen = ALUA_INQUIRY_SIZE;
return 1;
}
- h->bufflen = len;
+ pg->bufflen = len;
return 0;
}
+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);
+ if (pg->buff && pg->inq != pg->buff)
+ kfree(pg->buff);
+ kfree(pg);
+}
+
/*
* submit_rtpg - Issue a REPORT TARGET GROUP STATES command
* @sdev: sdev the command should be sent to
@@ -160,6 +183,37 @@ static int submit_stpg(struct scsi_device *sdev, int
group_id,
}
/*
+ * alua_get_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_get_pg(struct scsi_device *sdev,
+ int group_id, int tpgs)
+{
+ struct alua_port_group *pg = NULL;
+
+ pg = kzalloc(sizeof(struct alua_port_group), GFP_KERNEL);
+ if (!pg)
+ return NULL;
+
+ pg->group_id = group_id;
+ pg->buff = pg->inq;
+ pg->bufflen = ALUA_INQUIRY_SIZE;
+ 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
*
@@ -330,7 +384,7 @@ 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;
@@ -340,13 +394,14 @@ 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);
retry:
- retval = submit_rtpg(sdev, h->buff, h->bufflen, &sense_hdr, h->flags);
+ retval = submit_rtpg(sdev, pg->buff, pg->bufflen,
+ &sense_hdr, pg->flags);
if (retval) {
if (!scsi_sense_valid(&sense_hdr)) {
@@ -366,10 +421,10 @@ 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;
}
/*
@@ -393,11 +448,11 @@ static int alua_rtpg(struct scsi_device *sdev, struct
alua_dh_data *h, int wait_
return SCSI_DH_IO;
}
- len = get_unaligned_be32(&h->buff[0]) + 4;
+ len = get_unaligned_be32(&pg->buff[0]) + 4;
- if (len > h->bufflen) {
+ if (len > pg->bufflen) {
/* Resubmit with the correct length */
- if (realloc_buffer(h, len)) {
+ if (realloc_buffer(pg, len)) {
sdev_printk(KERN_WARNING, sdev,
"%s: kmalloc buffer failed\n",__func__);
/* Temporary failure, bypass */
@@ -406,31 +461,33 @@ static int alua_rtpg(struct scsi_device *sdev, struct
alua_dh_data *h, int wait_
goto retry;
}
- 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];
+ orig_transition_tmo = pg->transition_tmo;
+ if ((pg->buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR &&
+ pg->buff[5] != 0)
+ pg->transition_tmo = pg->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)) {
+ if (wait_for_transition &&
+ (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 ((h->buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR)
+ if ((pg->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 = pg->buff + tpg_desc_tbl_off;
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);
@@ -438,8 +495,8 @@ 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',
@@ -448,7 +505,7 @@ 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)) {
@@ -463,7 +520,7 @@ 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 */
@@ -485,22 +542,22 @@ 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:
@@ -514,13 +571,13 @@ 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)) {
@@ -530,7 +587,7 @@ 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);
}
@@ -548,20 +605,24 @@ 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_get_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;
}
@@ -577,6 +638,7 @@ 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;
@@ -589,10 +651,14 @@ 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;
}
@@ -617,16 +683,23 @@ 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);
@@ -642,13 +715,19 @@ 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;
}
@@ -663,20 +742,18 @@ 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->buff = h->inq;
- h->bufflen = ALUA_INQUIRY_SIZE;
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;
@@ -684,7 +761,7 @@ static int alua_bus_attach(struct scsi_device *sdev)
return 0;
failed:
kfree(h);
- return -EINVAL;
+ return ret;
}
/*
@@ -695,8 +772,10 @@ 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);
+ 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
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