/*
* Engenio/LSI RDAC SCSI Device Handler
*
* Copyright (C) 2005 Mike Christie. All rights reserved.
* Copyright (C) Chandra Seetharaman, IBM Corp. 2007
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
*/
#include <scsi/scsi.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_dh.h>
#define RDAC_NAME "rdac"
/*
* LSI mode page stuff
*
* These struct definitions and the forming of the
* mode page were taken from the LSI RDAC 2.4 GPL'd
* driver, and then converted to Linux conventions.
*/
#define RDAC_QUIESCENCE_TIME 20;
/*
* Page Codes
*/
#define RDAC_PAGE_CODE_REDUNDANT_CONTROLLER 0x2c
/*
* Controller modes definitions
*/
#define RDAC_MODE_TRANSFER_SPECIFIED_LUNS 0x02
/*
* RDAC Options field
*/
#define RDAC_FORCED_QUIESENCE 0x02
#define RDAC_TIMEOUT (60 * HZ)
#define RDAC_RETRIES 3
struct rdac_mode_6_hdr {
u8 data_len;
u8 medium_type;
u8 device_params;
u8 block_desc_len;
};
struct rdac_mode_10_hdr {
u16 data_len;
u8 medium_type;
u8 device_params;
u16 reserved;
u16 block_desc_len;
};
struct rdac_mode_common {
u8 controller_serial[16];
u8 alt_controller_serial[16];
u8 rdac_mode[2];
u8 alt_rdac_mode[2];
u8 quiescence_timeout;
u8 rdac_options;
};
struct rdac_pg_legacy {
struct rdac_mode_6_hdr hdr;
u8 page_code;
u8 page_len;
struct rdac_mode_common common;
#define MODE6_MAX_LUN 32
u8 lun_table[MODE6_MAX_LUN];
u8 reserved2[32];
u8 reserved3;
u8 reserved4;
};
struct rdac_pg_expanded {
struct rdac_mode_10_hdr hdr;
u8 page_code;
u8 subpage_code;
u8 page_len[2];
struct rdac_mode_common common;
u8 lun_table[256];
u8 reserved3;
u8 reserved4;
};
struct c9_inquiry {
u8 peripheral_info;
u8 page_code; /* 0xC9 */
u8 reserved1;
u8 page_len;
u8 page_id[4]; /* "vace" */
u8 avte_cvp;
u8 path_prio;
u8 reserved2[38];
};
#define SUBSYS_ID_LEN 16
#define SLOT_ID_LEN 2
struct c4_inquiry {
u8 peripheral_info;
u8 page_code; /* 0xC4 */
u8 reserved1;
u8 page_len;
u8 page_id[4]; /* "subs" */
u8 subsys_id[SUBSYS_ID_LEN];
u8 revision[4];
u8 slot_id[SLOT_ID_LEN];
u8 reserved[2];
};
struct rdac_controller {
u8 subsys_id[SUBSYS_ID_LEN];
u8 slot_id[SLOT_ID_LEN];
int use_ms10;
struct kref kref;
struct list_head node; /* list of all controllers */
union {
struct rdac_pg_legacy legacy;
struct rdac_pg_expanded expanded;
} mode_select;
};
struct c8_inquiry {
u8 peripheral_info;
u8 page_code; /* 0xC8 */
u8 reserved1;
u8 page_len;
u8 page_id[4]; /* "edid" */
u8 reserved2[3];
u8 vol_uniq_id_len;
u8 vol_uniq_id[16];
u8 vol_user_label_len;
u8 vol_user_label[60];
u8 array_uniq_id_len;
u8 array_unique_id[16];
u8 array_user_label_len;
u8 array_user_label[60];
u8 lun[8];
};
struct c2_inquiry {
u8 peripheral_info;
u8 page_code; /* 0xC2 */
u8 reserved1;
u8 page_len;
u8 page_id[4]; /* "swr4" */
u8 sw_version[3];
u8 sw_date[3];
u8 features_enabled;
u8 max_lun_supported;
u8 partitions[239]; /* Total allocation length should be 0xFF */
};
struct rdac_dh_data {
struct rdac_controller *ctlr;
#define UNINITIALIZED_LUN (1 << 8)
unsigned lun;
#define RDAC_STATE_ACTIVE 0
#define RDAC_STATE_PASSIVE 1
unsigned char state;
unsigned char sense[SCSI_SENSE_BUFFERSIZE];
union {
struct c2_inquiry c2;
struct c4_inquiry c4;
struct c8_inquiry c8;
struct c9_inquiry c9;
} inq;
};
static LIST_HEAD(ctlr_list);
static DEFINE_SPINLOCK(list_lock);
static inline struct rdac_dh_data *get_rdac_data(struct scsi_device *sdev)
{
struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data;
BUG_ON(scsi_dh_data == NULL);
return ((struct rdac_dh_data *) scsi_dh_data->buf);
}
static struct request *get_rdac_req(struct scsi_device *sdev,
void *buffer, unsigned buflen, int rw)
{
struct request *rq;
struct request_queue *q = sdev->request_queue;
struct rdac_dh_data *h = get_rdac_data(sdev);
rq = blk_get_request(q, rw, GFP_KERNEL);
if (!rq) {
sdev_printk(KERN_INFO, sdev,
"get_rdac_req: blk_get_request failed.\n");
return NULL;
}
if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_KERNEL)) {
blk_put_request(rq);
sdev_printk(KERN_INFO, sdev,
"get_rdac_req: blk_rq_map_kern failed.\n");
return NULL;
}
memset(&rq->cmd, 0, BLK_MAX_CDB);
rq->sense = h->sense;
memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
rq->sense_len = 0;
rq->cmd_type = REQ_TYPE_BLOCK_PC;
rq->cmd_flags |= REQ_FAILFAST | REQ_NOMERGE;
rq->retries = RDAC_RETRIES;
rq->timeout = RDAC_TIMEOUT;
return rq;
}
static struct request *rdac_failover_get(struct scsi_device *sdev)
{
struct request *rq;
struct rdac_mode_common *common;
unsigned data_size;
struct rdac_dh_data *h = get_rdac_data(sdev);
if (h->ctlr->use_ms10) {
struct rdac_pg_expanded *rdac_pg;
data_size = sizeof(struct rdac_pg_expanded);
rdac_pg = &h->ctlr->mode_select.expanded;
memset(rdac_pg, 0, data_size);
common = &rdac_pg->common;
rdac_pg->page_code = RDAC_PAGE_CODE_REDUNDANT_CONTROLLER + 0x40;
rdac_pg->subpage_code = 0x1;
rdac_pg->page_len[0] = 0x01;
rdac_pg->page_len[1] = 0x28;
rdac_pg->lun_table[h->lun] = 0x81;
} else {
struct rdac_pg_legacy *rdac_pg;
data_size = sizeof(struct rdac_pg_legacy);
rdac_pg = &h->ctlr->mode_select.legacy;
memset(rdac_pg, 0, data_size);
common = &rdac_pg->common;
rdac_pg->page_code = RDAC_PAGE_CODE_REDUNDANT_CONTROLLER;
rdac_pg->page_len = 0x68;
rdac_pg->lun_table[h->lun] = 0x81;
}
common->rdac_mode[1] = RDAC_MODE_TRANSFER_SPECIFIED_LUNS;
common->quiescence_timeout = RDAC_QUIESCENCE_TIME;
common->rdac_options = RDAC_FORCED_QUIESENCE;
/* get request for block layer packet command */
rq = get_rdac_req(sdev, &h->ctlr->mode_select, data_size, WRITE);
if (!rq)
return NULL;
/* Prepare the command. */
if (h->ctlr->use_ms10) {
rq->cmd[0] = MODE_SELECT_10;
rq->cmd[7] = data_size >> 8;
rq->cmd[8] = data_size & 0xff;
} else {
rq->cmd[0] = MODE_SELECT;
rq->cmd[4] = data_size;
}
rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
return rq;
}
static void release_controller(struct kref *kref)
{
struct rdac_controller *ctlr;
ctlr = container_of(kref, struct rdac_controller, kref);
spin_lock(&list_lock);
list_del(&ctlr->node);
spin_unlock(&list_lock);
kfree(ctlr);
}
static struct rdac_controller *get_controller(u8 *subsys_id, u8 *slot_id)
{
struct rdac_controller *ctlr, *tmp;
spin_lock(&list_lock);
list_for_each_entry(tmp, &ctlr_list, node) {
if ((memcmp(tmp->subsys_id, subsys_id, SUBSYS_ID_LEN) == 0) &&
(memcmp(tmp->slot_id, slot_id, SLOT_ID_LEN) == 0)) {
kref_get(&tmp->kref);
spin_unlock(&list_lock);
return tmp;
}
}
ctlr = kmalloc(sizeof(*ctlr), GFP_ATOMIC);
if (!ctlr)
goto done;
/* initialize fields of controller */
memcpy(ctlr->subsys_id, subsys_id, SUBSYS_ID_LEN);
memcpy(ctlr->slot_id, slot_id, SLOT_ID_LEN);
kref_init(&ctlr->kref);
ctlr->use_ms10 = -1;
list_add(&ctlr->node, &ctlr_list);
done:
spin_unlock(&list_lock);
return ctlr;
}
static int submit_inquiry(struct scsi_device *sdev, int page_code,
unsigned int len)
{
struct request *rq;
struct request_queue *q = sdev->request_queue;
struct rdac_dh_data *h = get_rdac_data(sdev);
int err = SCSI_DH_RES_TEMP_UNAVAIL;
rq = get_rdac_req(sdev, &h->inq, len, READ);
if (!rq)
goto done;
/* Prepare the command. */
rq->cmd[0] = INQUIRY;
rq->cmd[1] = 1;
rq->cmd[2] = page_code;
rq->cmd[4] = len;
rq->cmd_len = COMMAND_SIZE(INQUIRY);
err = blk_execute_rq(q, NULL, rq, 1);
if (err == -EIO)
err = SCSI_DH_IO;
done:
return err;
}
static int get_lun(struct scsi_device *sdev)
{
int err;
struct c8_inquiry *inqp;
struct rdac_dh_data *h = get_rdac_data(sdev);
err = submit_inquiry(sdev, 0xC8, sizeof(struct c8_inquiry));
if (err == SCSI_DH_OK) {
inqp = &h->inq.c8;
h->lun = inqp->lun[7]; /* currently it uses only one byte */
}
return err;
}
#define RDAC_OWNED 0
#define RDAC_UNOWNED 1
#define RDAC_FAILED 2
static int check_ownership(struct scsi_device *sdev)
{
int err;
struct c9_inquiry *inqp;
struct rdac_dh_data *h = get_rdac_data(sdev);
err = submit_inquiry(sdev, 0xC9, sizeof(struct c9_inquiry));
if (err == SCSI_DH_OK) {
err = RDAC_UNOWNED;
inqp = &h->inq.c9;
/*
* If in AVT mode or if the path already owns the LUN,
* return RDAC_OWNED;
*/
if (((inqp->avte_cvp >> 7) == 0x1) ||
((inqp->avte_cvp & 0x1) != 0))
err = RDAC_OWNED;
} else
err = RDAC_FAILED;
return err;
}
static int initialize_controller(struct scsi_device *sdev)
{
int err;
struct c4_inquiry *inqp;
struct rdac_dh_data *h = get_rdac_data(sdev);
err = submit_inquiry(sdev, 0xC4, sizeof(struct c4_inquiry));
if (err == SCSI_DH_OK) {
inqp = &h->inq.c4;
h->ctlr = get_controller(inqp->subsys_id, inqp->slot_id);
if (!h->ctlr)
err = SCSI_DH_RES_TEMP_UNAVAIL;
}
return err;
}
static int set_mode_select(struct scsi_device *sdev)
{
int err;
struct c2_inquiry *inqp;
struct rdac_dh_data *h = get_rdac_data(sdev);
err = submit_inquiry(sdev, 0xC2, sizeof(struct c2_inquiry));
if (err == SCSI_DH_OK) {
inqp = &h->inq.c2;
/*
* If more than MODE6_MAX_LUN luns are supported, use
* mode select 10
*/
if (inqp->max_lun_supported >= MODE6_MAX_LUN)
h->ctlr->use_ms10 = 1;
else
h->ctlr->use_ms10 = 0;
}
return err;
}
static int mode_select_handle_sense(struct scsi_device *sdev)
{
struct scsi_sense_hdr sense_hdr;
struct rdac_dh_data *h = get_rdac_data(sdev);
int sense, err = SCSI_DH_IO, ret;
ret = scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE, &sense_hdr);
if (!ret)
goto done;
err = SCSI_DH_OK;
sense = (sense_hdr.sense_key << 16) | (sense_hdr.asc << 8) |
sense_hdr.ascq;
/* If it is retryable failure, submit the c9 inquiry again */
if (sense == 0x59136 || sense == 0x68b02 || sense == 0xb8b02 ||
sense == 0x62900) {
/* 0x59136 - Command lock contention
* 0x[6b]8b02 - Quiesense in progress or achieved
* 0x62900 - Power On, Reset, or Bus Device Reset
*/
err = SCSI_DH_RETRY;
}
if (sense)
sdev_printk(KERN_INFO, sdev,
"MODE_SELECT failed with sense 0x%x.\n", sense);
done:
return err;
}
static int send_mode_select(struct scsi_device *sdev)
{
struct request *rq;
struct request_queue *q = sdev->request_queue;
struct rdac_dh_data *h = get_rdac_data(sdev);
int err = SCSI_DH_RES_TEMP_UNAVAIL;
rq = rdac_failover_get(sdev);
if (!rq)
goto done;
sdev_printk(KERN_INFO, sdev, "queueing MODE_SELECT command.\n");
err = blk_execute_rq(q, NULL, rq, 1);
if (err != SCSI_DH_OK)
err = mode_select_handle_sense(sdev);
if (err == SCSI_DH_OK)
h->state = RDAC_STATE_ACTIVE;
done:
return err;
}
static int rdac_activate(struct scsi_device *sdev)
{
struct rdac_dh_data *h = get_rdac_data(sdev);
int err = SCSI_DH_OK;
if (h->lun == UNINITIALIZED_LUN) {
err = get_lun(sdev);
if (err != SCSI_DH_OK)
goto done;
}
err = check_ownership(sdev);
switch (err) {
case RDAC_UNOWNED:
break;
case RDAC_OWNED:
err = SCSI_DH_OK;
goto done;
case RDAC_FAILED:
default:
err = SCSI_DH_IO;
goto done;
}
if (!h->ctlr) {
err = initialize_controller(sdev);
if (err != SCSI_DH_OK)
goto done;
}
if (h->ctlr->use_ms10 == -1) {
err = set_mode_select(sdev);
if (err != SCSI_DH_OK)
goto done;
}
err = send_mode_select(sdev);
done:
return err;
}
static int rdac_prep_fn(struct scsi_device *sdev, struct request *req)
{
struct rdac_dh_data *h = get_rdac_data(sdev);
int ret = BLKPREP_OK;
if (h->state != RDAC_STATE_ACTIVE) {
ret = BLKPREP_KILL;
req->cmd_flags |= REQ_QUIET;
}
return ret;
}
static int rdac_check_sense(struct scsi_device *sdev,
struct scsi_sense_hdr *sense_hdr)
{
struct rdac_dh_data *h = get_rdac_data(sdev);
switch (sense_hdr->sense_key) {
case NOT_READY:
if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x81)
/* LUN Not Ready - Storage firmware incompatible
* Manual code synchonisation required.
*
* Nothing we can do here. Try to bypass the path.
*/
return SUCCESS;
if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0xA1)
/* LUN Not Ready - Quiescense in progress
*
* Just retry and wait.
*/
return NEEDS_RETRY;
break;
case ILLEGAL_REQUEST:
if (sense_hdr->asc == 0x94 && sense_hdr->ascq == 0x01) {
/* Invalid Request - Current Logical Unit Ownership.
* Controller is not the current owner of the LUN,
* Fail the path, so that the other path be used.
*/
h->state = RDAC_STATE_PASSIVE;
return SUCCESS;
}
break;
case UNIT_ATTENTION:
if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00)
/*
* Power On, Reset, or Bus Device Reset, just retry.
*/
return NEEDS_RETRY;
break;
}
/* success just means we do not care what scsi-ml does */
return SCSI_RETURN_NOT_HANDLED;
}
static const struct {
char *vendor;
char *model;
} rdac_dev_list[] = {
{"IBM", "1722"},
{"IBM", "1724"},
{"IBM", "1726"},
{"IBM", "1742"},
{"IBM", "1814"},
{"IBM", "1815"},
{"IBM", "1818"},
{"IBM", "3526"},
{"SGI", "TP9400"},
{"SGI", "TP9500"},
{"SGI", "IS"},
{"STK", "OPENstorage D280"},
{"SUN", "CSM200_R"},
{"SUN", "LCSM100_F"},
{NULL, NULL},
};
static int rdac_bus_notify(struct notifier_block *, unsigned long, void *);
static struct scsi_device_handler rdac_dh = {
.name = RDAC_NAME,
.module = THIS_MODULE,
.nb.notifier_call = rdac_bus_notify,
.prep_fn = rdac_prep_fn,
.check_sense = rdac_check_sense,
.activate = rdac_activate,
};
/*
* TODO: need some interface so we can set trespass values
*/
static int rdac_bus_notify(struct notifier_block *nb,
unsigned long action, void *data)
{
struct device *dev = data;
struct scsi_device *sdev;
struct scsi_dh_data *scsi_dh_data;
struct rdac_dh_data *h;
int i, found = 0;
unsigned long flags;
if (!scsi_is_sdev_device(dev))
return 0;
sdev = to_scsi_device(dev);
if (action == BUS_NOTIFY_ADD_DEVICE) {
for (i = 0; rdac_dev_list[i].vendor; i++) {
if (!strncmp(sdev->vendor, rdac_dev_list[i].vendor,
strlen(rdac_dev_list[i].vendor)) &&
!strncmp(sdev->model, rdac_dev_list[i].model,
strlen(rdac_dev_list[i].model))) {
found = 1;
break;
}
}
if (!found)
goto out;
scsi_dh_data = kzalloc(sizeof(struct scsi_device_handler *)
+ sizeof(*h) , GFP_KERNEL);
if (!scsi_dh_data) {
sdev_printk(KERN_ERR, sdev, "Attach failed %s.\n",
RDAC_NAME);
goto out;
}
scsi_dh_data->scsi_dh = &rdac_dh;
h = (struct rdac_dh_data *) scsi_dh_data->buf;
h->lun = UNINITIALIZED_LUN;
h->state = RDAC_STATE_ACTIVE;
spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
sdev->scsi_dh_data = scsi_dh_data;
spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
try_module_get(THIS_MODULE);
sdev_printk(KERN_NOTICE, sdev, "Attached %s.\n", RDAC_NAME);
} else if (action == BUS_NOTIFY_DEL_DEVICE) {
if (sdev->scsi_dh_data == NULL ||
sdev->scsi_dh_data->scsi_dh != &rdac_dh)
goto out;
spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
scsi_dh_data = sdev->scsi_dh_data;
sdev->scsi_dh_data = NULL;
spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
h = (struct rdac_dh_data *) scsi_dh_data->buf;
if (h->ctlr)
kref_put(&h->ctlr->kref, release_controller);
kfree(scsi_dh_data);
module_put(THIS_MODULE);
sdev_printk(KERN_NOTICE, sdev, "Dettached %s.\n", RDAC_NAME);
}
out:
return 0;
}
static int __init rdac_init(void)
{
int r;
r = scsi_register_device_handler(&rdac_dh);
if (r != 0)
printk(KERN_ERR "Failed to register scsi device handler.");
return r;
}
static void __exit rdac_exit(void)
{
scsi_unregister_device_handler(&rdac_dh);
}
module_init(rdac_init);
module_exit(rdac_exit);
MODULE_DESCRIPTION("Multipath LSI/Engenio RDAC driver");
MODULE_AUTHOR("Mike Christie, Chandra Seetharaman");
MODULE_LICENSE("GPL");
