#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;
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
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
ALUA_DH_NAME);
return SCSI_DH_DEV_UNSUPP;
}
- h->state = TPGS_STATE_OPTIMIZED;
h->group_id = group_id;
sdev_printk(KERN_INFO, 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;
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)) {
* 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;
}
/*
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)
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);
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',
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)) {
}
/* Transitioning time exceeded, set port to standby */
- h->state = TPGS_STATE_STANDBY;
+ pg->state = TPGS_STATE_STANDBY;
break;
case TPGS_STATE_OFFLINE:
/* Path unusable */
* 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:
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)) {
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);
}
*/
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;
}
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;
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;
}
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);
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;
}
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;
return 0;
failed:
kfree(h);
- return -EINVAL;
+ return ret;
}
/*
{
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);
}
projects / cascardo / linux.git / commitdiff