- 根目录:
- drivers
- scsi
- device_handler
- scsi_dh_hp_sw.c
/*
* Basic HP/COMPAQ MSA 1000 support. This is only needed if your HW cannot be
* upgraded.
*
* Copyright (C) 2006 Red Hat, Inc. All rights reserved.
* Copyright (C) 2006 Mike Christie
* Copyright (C) 2008 Hannes Reinecke <hare@suse.de>
*
* 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, 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; see the file COPYING. If not, write to
* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/slab.h>
#include <linux/module.h>
#include <scsi/scsi.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_dh.h>
#define HP_SW_NAME "hp_sw"
#define HP_SW_TIMEOUT (60 * HZ)
#define HP_SW_RETRIES 3
#define HP_SW_PATH_UNINITIALIZED -1
#define HP_SW_PATH_ACTIVE 0
#define HP_SW_PATH_PASSIVE 1
struct hp_sw_dh_data {
unsigned char sense[SCSI_SENSE_BUFFERSIZE];
int path_state;
int retries;
int retry_cnt;
struct scsi_device *sdev;
activate_complete callback_fn;
void *callback_data;
};
static int hp_sw_start_stop(struct hp_sw_dh_data *);
static inline struct hp_sw_dh_data *get_hp_sw_data(struct scsi_device *sdev)
{
struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data;
BUG_ON(scsi_dh_data == NULL);
return ((struct hp_sw_dh_data *) scsi_dh_data->buf);
}
/*
* tur_done - Handle TEST UNIT READY return status
* @sdev: sdev the command has been sent to
* @errors: blk error code
*
* Returns SCSI_DH_DEV_OFFLINED if the sdev is on the passive path
*/
static int tur_done(struct scsi_device *sdev, unsigned char *sense)
{
struct scsi_sense_hdr sshdr;
int ret;
ret = scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr);
if (!ret) {
sdev_printk(KERN_WARNING, sdev,
"%s: sending tur failed, no sense available\n",
HP_SW_NAME);
ret = SCSI_DH_IO;
goto done;
}
switch (sshdr.sense_key) {
case UNIT_ATTENTION:
ret = SCSI_DH_IMM_RETRY;
break;
case NOT_READY:
if ((sshdr.asc == 0x04) && (sshdr.ascq == 2)) {
/*
* LUN not ready - Initialization command required
*
* This is the passive path
*/
ret = SCSI_DH_DEV_OFFLINED;
break;
}
/* Fallthrough */
default:
sdev_printk(KERN_WARNING, sdev,
"%s: sending tur failed, sense %x/%x/%x\n",
HP_SW_NAME, sshdr.sense_key, sshdr.asc,
sshdr.ascq);
break;
}
done:
return ret;
}
/*
* hp_sw_tur - Send TEST UNIT READY
* @sdev: sdev command should be sent to
*
* Use the TEST UNIT READY command to determine
* the path state.
*/
static int hp_sw_tur(struct scsi_device *sdev, struct hp_sw_dh_data *h)
{
struct request *req;
int ret;
retry:
req = blk_get_request(sdev->request_queue, WRITE, GFP_NOIO);
if (!req)
return SCSI_DH_RES_TEMP_UNAVAIL;
req->cmd_type = REQ_TYPE_BLOCK_PC;
req->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
REQ_FAILFAST_DRIVER;
req->cmd_len = COMMAND_SIZE(TEST_UNIT_READY);
req->cmd[0] = TEST_UNIT_READY;
req->timeout = HP_SW_TIMEOUT;
req->sense = h->sense;
memset(req->sense, 0, SCSI_SENSE_BUFFERSIZE);
req->sense_len = 0;
ret = blk_execute_rq(req->q, NULL, req, 1);
if (ret == -EIO) {
if (req->sense_len > 0) {
ret = tur_done(sdev, h->sense);
} else {
sdev_printk(KERN_WARNING, sdev,
"%s: sending tur failed with %x\n",
HP_SW_NAME, req->errors);
ret = SCSI_DH_IO;
}
} else {
h->path_state = HP_SW_PATH_ACTIVE;
ret = SCSI_DH_OK;
}
if (ret == SCSI_DH_IMM_RETRY) {
blk_put_request(req);
goto retry;
}
if (ret == SCSI_DH_DEV_OFFLINED) {
h->path_state = HP_SW_PATH_PASSIVE;
ret = SCSI_DH_OK;
}
blk_put_request(req);
return ret;
}
/*
* start_done - Handle START STOP UNIT return status
* @sdev: sdev the command has been sent to
* @errors: blk error code
*/
static int start_done(struct scsi_device *sdev, unsigned char *sense)
{
struct scsi_sense_hdr sshdr;
int rc;
rc = scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr);
if (!rc) {
sdev_printk(KERN_WARNING, sdev,
"%s: sending start_stop_unit failed, "
"no sense available\n",
HP_SW_NAME);
return SCSI_DH_IO;
}
switch (sshdr.sense_key) {
case NOT_READY:
if ((sshdr.asc == 0x04) && (sshdr.ascq == 3)) {
/*
* LUN not ready - manual intervention required
*
* Switch-over in progress, retry.
*/
rc = SCSI_DH_RETRY;
break;
}
/* fall through */
default:
sdev_printk(KERN_WARNING, sdev,
"%s: sending start_stop_unit failed, sense %x/%x/%x\n",
HP_SW_NAME, sshdr.sense_key, sshdr.asc,
sshdr.ascq);
rc = SCSI_DH_IO;
}
return rc;
}
static void start_stop_endio(struct request *req, int error)
{
struct hp_sw_dh_data *h = req->end_io_data;
unsigned err = SCSI_DH_OK;
if (error || host_byte(req->errors) != DID_OK ||
msg_byte(req->errors) != COMMAND_COMPLETE) {
sdev_printk(KERN_WARNING, h->sdev,
"%s: sending start_stop_unit failed with %x\n",
HP_SW_NAME, req->errors);
err = SCSI_DH_IO;
goto done;
}
if (req->sense_len > 0) {
err = start_done(h->sdev, h->sense);
if (err == SCSI_DH_RETRY) {
err = SCSI_DH_IO;
if (--h->retry_cnt) {
blk_put_request(req);
err = hp_sw_start_stop(h);
if (err == SCSI_DH_OK)
return;
}
}
}
done:
req->end_io_data = NULL;
__blk_put_request(req->q, req);
if (h->callback_fn) {
h->callback_fn(h->callback_data, err);
h->callback_fn = h->callback_data = NULL;
}
return;
}
/*
* hp_sw_start_stop - Send START STOP UNIT command
* @sdev: sdev command should be sent to
*
* Sending START STOP UNIT activates the SP.
*/
static int hp_sw_start_stop(struct hp_sw_dh_data *h)
{
struct request *req;
req = blk_get_request(h->sdev->request_queue, WRITE, GFP_ATOMIC);
if (!req)
return SCSI_DH_RES_TEMP_UNAVAIL;
req->cmd_type = REQ_TYPE_BLOCK_PC;
req->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
REQ_FAILFAST_DRIVER;
req->cmd_len = COMMAND_SIZE(START_STOP);
req->cmd[0] = START_STOP;
req->cmd[4] = 1; /* Start spin cycle */
req->timeout = HP_SW_TIMEOUT;
req->sense = h->sense;
memset(req->sense, 0, SCSI_SENSE_BUFFERSIZE);
req->sense_len = 0;
req->end_io_data = h;
blk_execute_rq_nowait(req->q, NULL, req, 1, start_stop_endio);
return SCSI_DH_OK;
}
static int hp_sw_prep_fn(struct scsi_device *sdev, struct request *req)
{
struct hp_sw_dh_data *h = get_hp_sw_data(sdev);
int ret = BLKPREP_OK;
if (h->path_state != HP_SW_PATH_ACTIVE) {
ret = BLKPREP_KILL;
req->cmd_flags |= REQ_QUIET;
}
return ret;
}
/*
* hp_sw_activate - Activate a path
* @sdev: sdev on the path to be activated
*
* The HP Active/Passive firmware is pretty simple;
* the passive path reports NOT READY with sense codes
* 0x04/0x02; a START STOP UNIT command will then
* activate the passive path (and deactivate the
* previously active one).
*/
static int hp_sw_activate(struct scsi_device *sdev,
activate_complete fn, void *data)
{
int ret = SCSI_DH_OK;
struct hp_sw_dh_data *h = get_hp_sw_data(sdev);
ret = hp_sw_tur(sdev, h);
if (ret == SCSI_DH_OK && h->path_state == HP_SW_PATH_PASSIVE) {
h->retry_cnt = h->retries;
h->callback_fn = fn;
h->callback_data = data;
ret = hp_sw_start_stop(h);
if (ret == SCSI_DH_OK)
return 0;
h->callback_fn = h->callback_data = NULL;
}
if (fn)
fn(data, ret);
return 0;
}
static const struct scsi_dh_devlist hp_sw_dh_data_list[] = {
{"COMPAQ", "MSA1000 VOLUME"},
{"COMPAQ", "HSV110"},
{"HP", "HSV100"},
{"DEC", "HSG80"},
{NULL, NULL},
};
static bool hp_sw_match(struct scsi_device *sdev)
{
int i;
if (scsi_device_tpgs(sdev))
return false;
for (i = 0; hp_sw_dh_data_list[i].vendor; i++) {
if (!strncmp(sdev->vendor, hp_sw_dh_data_list[i].vendor,
strlen(hp_sw_dh_data_list[i].vendor)) &&
!strncmp(sdev->model, hp_sw_dh_data_list[i].model,
strlen(hp_sw_dh_data_list[i].model))) {
return true;
}
}
return false;
}
static int hp_sw_bus_attach(struct scsi_device *sdev);
static void hp_sw_bus_detach(struct scsi_device *sdev);
static struct scsi_device_handler hp_sw_dh = {
.name = HP_SW_NAME,
.module = THIS_MODULE,
.devlist = hp_sw_dh_data_list,
.attach = hp_sw_bus_attach,
.detach = hp_sw_bus_detach,
.activate = hp_sw_activate,
.prep_fn = hp_sw_prep_fn,
.match = hp_sw_match,
};
static int hp_sw_bus_attach(struct scsi_device *sdev)
{
struct scsi_dh_data *scsi_dh_data;
struct hp_sw_dh_data *h;
unsigned long flags;
int ret;
scsi_dh_data = kzalloc(sizeof(*scsi_dh_data)
+ sizeof(*h) , GFP_KERNEL);
if (!scsi_dh_data) {
sdev_printk(KERN_ERR, sdev, "%s: Attach Failed\n",
HP_SW_NAME);
return 0;
}
scsi_dh_data->scsi_dh = &hp_sw_dh;
h = (struct hp_sw_dh_data *) scsi_dh_data->buf;
h->path_state = HP_SW_PATH_UNINITIALIZED;
h->retries = HP_SW_RETRIES;
h->sdev = sdev;
ret = hp_sw_tur(sdev, h);
if (ret != SCSI_DH_OK || h->path_state == HP_SW_PATH_UNINITIALIZED)
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_INFO, sdev, "%s: attached to %s path\n",
HP_SW_NAME, h->path_state == HP_SW_PATH_ACTIVE?
"active":"passive");
return 0;
failed:
kfree(scsi_dh_data);
sdev_printk(KERN_ERR, sdev, "%s: not attached\n",
HP_SW_NAME);
return -EINVAL;
}
static void hp_sw_bus_detach( struct scsi_device *sdev )
{
struct scsi_dh_data *scsi_dh_data;
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);
module_put(THIS_MODULE);
sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n", HP_SW_NAME);
kfree(scsi_dh_data);
}
static int __init hp_sw_init(void)
{
return scsi_register_device_handler(&hp_sw_dh);
}
static void __exit hp_sw_exit(void)
{
scsi_unregister_device_handler(&hp_sw_dh);
}
module_init(hp_sw_init);
module_exit(hp_sw_exit);
MODULE_DESCRIPTION("HP Active/Passive driver");
MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu");
MODULE_LICENSE("GPL");