alistair23-linux/drivers/scsi/device_handler/scsi_dh_rdac.c
Chandra Seetharaman 5a36756b8b [SCSI] scsi_dh: Initialize path state to be passive when path is not owned
Set the path state to be passive when we learn that the controller does
not own the path to the LUN.

This will avoid sending even a single i/o thru the passive path at the
probe time.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-23 11:42:11 -05:00

704 lines
16 KiB
C

/*
* 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;
#define RDAC_LUN_UNOWNED 0
#define RDAC_LUN_OWNED 1
#define RDAC_LUN_AVT 2
char lun_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 const char *lun_state[] =
{
"unowned",
"owned",
"owned (AVT mode)",
};
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;
rq = blk_get_request(q, rw, GFP_NOIO);
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_NOIO)) {
blk_put_request(rq);
sdev_printk(KERN_INFO, sdev,
"get_rdac_req: blk_rq_map_kern failed.\n");
return NULL;
}
rq->cmd_type = REQ_TYPE_BLOCK_PC;
rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
REQ_FAILFAST_DRIVER;
rq->retries = RDAC_RETRIES;
rq->timeout = RDAC_TIMEOUT;
return rq;
}
static struct request *rdac_failover_get(struct scsi_device *sdev,
struct rdac_dh_data *h)
{
struct request *rq;
struct rdac_mode_common *common;
unsigned data_size;
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]);
rq->sense = h->sense;
memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
rq->sense_len = 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 rdac_dh_data *h)
{
struct request *rq;
struct request_queue *q = sdev->request_queue;
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);
rq->sense = h->sense;
memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
rq->sense_len = 0;
err = blk_execute_rq(q, NULL, rq, 1);
if (err == -EIO)
err = SCSI_DH_IO;
blk_put_request(rq);
done:
return err;
}
static int get_lun(struct scsi_device *sdev, struct rdac_dh_data *h)
{
int err;
struct c8_inquiry *inqp;
err = submit_inquiry(sdev, 0xC8, sizeof(struct c8_inquiry), h);
if (err == SCSI_DH_OK) {
inqp = &h->inq.c8;
if (inqp->page_code != 0xc8)
return SCSI_DH_NOSYS;
if (inqp->page_id[0] != 'e' || inqp->page_id[1] != 'd' ||
inqp->page_id[2] != 'i' || inqp->page_id[3] != 'd')
return SCSI_DH_NOSYS;
h->lun = inqp->lun[7]; /* Uses only the last byte */
}
return err;
}
static int check_ownership(struct scsi_device *sdev, struct rdac_dh_data *h)
{
int err;
struct c9_inquiry *inqp;
h->lun_state = RDAC_LUN_UNOWNED;
err = submit_inquiry(sdev, 0xC9, sizeof(struct c9_inquiry), h);
if (err == SCSI_DH_OK) {
inqp = &h->inq.c9;
if ((inqp->avte_cvp >> 7) == 0x1) {
/* LUN in AVT mode */
sdev_printk(KERN_NOTICE, sdev,
"%s: AVT mode detected\n",
RDAC_NAME);
h->lun_state = RDAC_LUN_AVT;
} else if ((inqp->avte_cvp & 0x1) != 0) {
/* LUN was owned by the controller */
h->lun_state = RDAC_LUN_OWNED;
}
}
if (h->lun_state == RDAC_LUN_UNOWNED)
h->state = RDAC_STATE_PASSIVE;
return err;
}
static int initialize_controller(struct scsi_device *sdev,
struct rdac_dh_data *h)
{
int err;
struct c4_inquiry *inqp;
err = submit_inquiry(sdev, 0xC4, sizeof(struct c4_inquiry), h);
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, struct rdac_dh_data *h)
{
int err;
struct c2_inquiry *inqp;
err = submit_inquiry(sdev, 0xC2, sizeof(struct c2_inquiry), h);
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,
unsigned char *sensebuf)
{
struct scsi_sense_hdr sense_hdr;
int sense, err = SCSI_DH_IO, ret;
ret = scsi_normalize_sense(sensebuf, 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 rdac_dh_data *h)
{
struct request *rq;
struct request_queue *q = sdev->request_queue;
int err = SCSI_DH_RES_TEMP_UNAVAIL;
rq = rdac_failover_get(sdev, h);
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, h->sense);
if (err == SCSI_DH_OK)
h->state = RDAC_STATE_ACTIVE;
blk_put_request(rq);
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;
err = check_ownership(sdev, h);
if (err != SCSI_DH_OK)
goto done;
if (!h->ctlr) {
err = initialize_controller(sdev, h);
if (err != SCSI_DH_OK)
goto done;
}
if (h->ctlr->use_ms10 == -1) {
err = set_mode_select(sdev, h);
if (err != SCSI_DH_OK)
goto done;
}
if (h->lun_state == RDAC_LUN_UNOWNED)
err = send_mode_select(sdev, h);
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 ADD_TO_MLQUEUE;
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 ADD_TO_MLQUEUE;
break;
}
/* success just means we do not care what scsi-ml does */
return SCSI_RETURN_NOT_HANDLED;
}
static const struct scsi_dh_devlist 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"},
{"DELL", "MD3000"},
{"DELL", "MD3000i"},
{NULL, NULL},
};
static int rdac_bus_attach(struct scsi_device *sdev);
static void rdac_bus_detach(struct scsi_device *sdev);
static struct scsi_device_handler rdac_dh = {
.name = RDAC_NAME,
.module = THIS_MODULE,
.devlist = rdac_dev_list,
.prep_fn = rdac_prep_fn,
.check_sense = rdac_check_sense,
.attach = rdac_bus_attach,
.detach = rdac_bus_detach,
.activate = rdac_activate,
};
static int rdac_bus_attach(struct scsi_device *sdev)
{
struct scsi_dh_data *scsi_dh_data;
struct rdac_dh_data *h;
unsigned long flags;
int err;
scsi_dh_data = kzalloc(sizeof(struct scsi_device_handler *)
+ sizeof(*h) , GFP_KERNEL);
if (!scsi_dh_data) {
sdev_printk(KERN_ERR, sdev, "%s: Attach failed\n",
RDAC_NAME);
return 0;
}
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;
err = get_lun(sdev, h);
if (err != SCSI_DH_OK)
goto failed;
err = check_ownership(sdev, h);
if (err != SCSI_DH_OK)
goto failed;
if (!try_module_get(THIS_MODULE))
goto failed;
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);
sdev_printk(KERN_NOTICE, sdev,
"%s: LUN %d (%s)\n",
RDAC_NAME, h->lun, lun_state[(int)h->lun_state]);
return 0;
failed:
kfree(scsi_dh_data);
sdev_printk(KERN_ERR, sdev, "%s: not attached\n",
RDAC_NAME);
return -EINVAL;
}
static void rdac_bus_detach( struct scsi_device *sdev )
{
struct scsi_dh_data *scsi_dh_data;
struct rdac_dh_data *h;
unsigned long flags;
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, "%s: Detached\n", RDAC_NAME);
}
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");