/*
* Target driver for EMC CLARiiON AX/CX-series hardware.
* Based on code from Lars Marowsky-Bree <lmb@suse.de>
* and Ed Goggin <egoggin@emc.com>.
*
* Copyright (C) 2006 Red Hat, Inc. All rights reserved.
* Copyright (C) 2006 Mike Christie
*
* 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 <scsi/scsi.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_dh.h>
#include <scsi/scsi_device.h>
#define CLARIION_NAME "emc_clariion"
#define CLARIION_TRESPASS_PAGE 0x22
#define CLARIION_BUFFER_SIZE 0x80
#define CLARIION_TIMEOUT (60 * HZ)
#define CLARIION_RETRIES 3
#define CLARIION_UNBOUND_LU -1
static unsigned char long_trespass[] = {
0, 0, 0, 0,
CLARIION_TRESPASS_PAGE, /* Page code */
0x09, /* Page length - 2 */
0x81, /* Trespass code + Honor reservation bit */
0xff, 0xff, /* Trespass target */
0, 0, 0, 0, 0, 0 /* Reserved bytes / unknown */
};
static unsigned char long_trespass_hr[] = {
0, 0, 0, 0,
CLARIION_TRESPASS_PAGE, /* Page code */
0x09, /* Page length - 2 */
0x01, /* Trespass code + Honor reservation bit */
0xff, 0xff, /* Trespass target */
0, 0, 0, 0, 0, 0 /* Reserved bytes / unknown */
};
static unsigned char short_trespass[] = {
0, 0, 0, 0,
CLARIION_TRESPASS_PAGE, /* Page code */
0x02, /* Page length - 2 */
0x81, /* Trespass code + Honor reservation bit */
0xff, /* Trespass target */
};
static unsigned char short_trespass_hr[] = {
0, 0, 0, 0,
CLARIION_TRESPASS_PAGE, /* Page code */
0x02, /* Page length - 2 */
0x01, /* Trespass code + Honor reservation bit */
0xff, /* Trespass target */
};
struct clariion_dh_data {
/*
* Use short trespass command (FC-series) or the long version
* (default for AX/CX CLARiiON arrays).
*/
unsigned short_trespass;
/*
* Whether or not (default) to honor SCSI reservations when
* initiating a switch-over.
*/
unsigned hr;
/* I/O buffer for both MODE_SELECT and INQUIRY commands. */
char buffer[CLARIION_BUFFER_SIZE];
/*
* SCSI sense buffer for commands -- assumes serial issuance
* and completion sequence of all commands for same multipath.
*/
unsigned char sense[SCSI_SENSE_BUFFERSIZE];
/* which SP (A=0,B=1,UNBOUND=-1) is dflt SP for path's mapped dev */
int default_sp;
/* which SP (A=0,B=1,UNBOUND=-1) is active for path's mapped dev */
int current_sp;
};
static inline struct clariion_dh_data
*get_clariion_data(struct scsi_device *sdev)
{
struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data;
BUG_ON(scsi_dh_data == NULL);
return ((struct clariion_dh_data *) scsi_dh_data->buf);
}
/*
* Parse MODE_SELECT cmd reply.
*/
static int trespass_endio(struct scsi_device *sdev, int result)
{
int err = SCSI_DH_OK;
struct scsi_sense_hdr sshdr;
struct clariion_dh_data *csdev = get_clariion_data(sdev);
char *sense = csdev->sense;
if (status_byte(result) == CHECK_CONDITION &&
scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)) {
sdev_printk(KERN_ERR, sdev, "Found valid sense data 0x%2x, "
"0x%2x, 0x%2x while sending CLARiiON trespass "
"command.\n", sshdr.sense_key, sshdr.asc,
sshdr.ascq);
if ((sshdr.sense_key == 0x05) && (sshdr.asc == 0x04) &&
(sshdr.ascq == 0x00)) {
/*
* Array based copy in progress -- do not send
* mode_select or copy will be aborted mid-stream.
*/
sdev_printk(KERN_INFO, sdev, "Array Based Copy in "
"progress while sending CLARiiON trespass "
"command.\n");
err = SCSI_DH_DEV_TEMP_BUSY;
} else if ((sshdr.sense_key == 0x02) && (sshdr.asc == 0x04) &&
(sshdr.ascq == 0x03)) {
/*
* LUN Not Ready - Manual Intervention Required
* indicates in-progress ucode upgrade (NDU).
*/
sdev_printk(KERN_INFO, sdev, "Detected in-progress "
"ucode upgrade NDU operation while sending "
"CLARiiON trespass command.\n");
err = SCSI_DH_DEV_TEMP_BUSY;
} else
err = SCSI_DH_DEV_FAILED;
} else if (result) {
sdev_printk(KERN_ERR, sdev, "Error 0x%x while sending "
"CLARiiON trespass command.\n", result);
err = SCSI_DH_IO;
}
return err;
}
static int parse_sp_info_reply(struct scsi_device *sdev, int result,
int *default_sp, int *current_sp, int *new_current_sp)
{
int err = SCSI_DH_OK;
struct clariion_dh_data *csdev = get_clariion_data(sdev);
if (result == 0) {
/* check for in-progress ucode upgrade (NDU) */
if (csdev->buffer[48] != 0) {
sdev_printk(KERN_NOTICE, sdev, "Detected in-progress "
"ucode upgrade NDU operation while finding "
"current active SP.");
err = SCSI_DH_DEV_TEMP_BUSY;
} else {
*default_sp = csdev->buffer[5];
if (csdev->buffer[4] == 2)
/* SP for path is current */
*current_sp = csdev->buffer[8];
else {
if (csdev->buffer[4] == 1)
/* SP for this path is NOT current */
if (csdev->buffer[8] == 0)
*current_sp = 1;
else
*current_sp = 0;
else
/* unbound LU or LUNZ */
*current_sp = CLARIION_UNBOUND_LU;
}
*new_current_sp = csdev->buffer[8];
}
} else {
struct scsi_sense_hdr sshdr;
err = SCSI_DH_IO;
if (scsi_normalize_sense(csdev->sense, SCSI_SENSE_BUFFERSIZE,
&sshdr))
sdev_printk(KERN_ERR, sdev, "Found valid sense data "
"0x%2x, 0x%2x, 0x%2x while finding current "
"active SP.", sshdr.sense_key, sshdr.asc,
sshdr.ascq);
else
sdev_printk(KERN_ERR, sdev, "Error 0x%x finding "
"current active SP.", result);
}
return err;
}
static int sp_info_endio(struct scsi_device *sdev, int result,
int mode_select_sent, int *done)
{
struct clariion_dh_data *csdev = get_clariion_data(sdev);
int err_flags, default_sp, current_sp, new_current_sp;
err_flags = parse_sp_info_reply(sdev, result, &default_sp,
¤t_sp, &new_current_sp);
if (err_flags != SCSI_DH_OK)
goto done;
if (mode_select_sent) {
csdev->default_sp = default_sp;
csdev->current_sp = current_sp;
} else {
/*
* Issue the actual module_selec request IFF either
* (1) we do not know the identity of the current SP OR
* (2) what we think we know is actually correct.
*/
if ((current_sp != CLARIION_UNBOUND_LU) &&
(new_current_sp != current_sp)) {
csdev->default_sp = default_sp;
csdev->current_sp = current_sp;
sdev_printk(KERN_INFO, sdev, "Ignoring path group "
"switch-over command for CLARiiON SP%s since "
" mapped device is already initialized.",
current_sp ? "B" : "A");
if (done)
*done = 1; /* as good as doing it */
}
}
done:
return err_flags;
}
/*
* Get block request for REQ_BLOCK_PC command issued to path. Currently
* limited to MODE_SELECT (trespass) and INQUIRY (VPD page 0xC0) commands.
*
* Uses data and sense buffers in hardware handler context structure and
* assumes serial servicing of commands, both issuance and completion.
*/
static struct request *get_req(struct scsi_device *sdev, int cmd)
{
struct clariion_dh_data *csdev = get_clariion_data(sdev);
struct request *rq;
unsigned char *page22;
int len = 0;
rq = blk_get_request(sdev->request_queue,
(cmd == MODE_SELECT) ? WRITE : READ, GFP_ATOMIC);
if (!rq) {
sdev_printk(KERN_INFO, sdev, "get_req: blk_get_request failed");
return NULL;
}
memset(&rq->cmd, 0, BLK_MAX_CDB);
rq->cmd[0] = cmd;
rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
switch (cmd) {
case MODE_SELECT:
if (csdev->short_trespass) {
page22 = csdev->hr ? short_trespass_hr : short_trespass;
len = sizeof(short_trespass);
} else {
page22 = csdev->hr ? long_trespass_hr : long_trespass;
len = sizeof(long_trespass);
}
/*
* Can't DMA from kernel BSS -- must copy selected trespass
* command mode page contents to context buffer which is
* allocated by kmalloc.
*/
BUG_ON((len > CLARIION_BUFFER_SIZE));
memcpy(csdev->buffer, page22, len);
rq->cmd_flags |= REQ_RW;
rq->cmd[1] = 0x10;
break;
case INQUIRY:
rq->cmd[1] = 0x1;
rq->cmd[2] = 0xC0;
len = CLARIION_BUFFER_SIZE;
memset(csdev->buffer, 0, CLARIION_BUFFER_SIZE);
break;
default:
BUG_ON(1);
break;
}
rq->cmd[4] = len;
rq->cmd_type = REQ_TYPE_BLOCK_PC;
rq->cmd_flags |= REQ_FAILFAST;
rq->timeout = CLARIION_TIMEOUT;
rq->retries = CLARIION_RETRIES;
rq->sense = csdev->sense;
memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
rq->sense_len = 0;
if (blk_rq_map_kern(sdev->request_queue, rq, csdev->buffer,
len, GFP_ATOMIC)) {
__blk_put_request(rq->q, rq);
return NULL;
}
return rq;
}
static int send_cmd(struct scsi_device *sdev, int cmd)
{
struct request *rq = get_req(sdev, cmd);
if (!rq)
return SCSI_DH_RES_TEMP_UNAVAIL;
return blk_execute_rq(sdev->request_queue, NULL, rq, 1);
}
static int clariion_activate(struct scsi_device *sdev)
{
int result, done = 0;
result = send_cmd(sdev, INQUIRY);
result = sp_info_endio(sdev, result, 0, &done);
if (result || done)
goto done;
result = send_cmd(sdev, MODE_SELECT);
result = trespass_endio(sdev, result);
if (result)
goto done;
result = send_cmd(sdev, INQUIRY);
result = sp_info_endio(sdev, result, 1, NULL);
done:
return result;
}
static int clariion_check_sense(struct scsi_device *sdev,
struct scsi_sense_hdr *sense_hdr)
{
switch (sense_hdr->sense_key) {
case NOT_READY:
if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x03)
/*
* LUN Not Ready - Manual Intervention Required
* indicates this is a passive path.
*
* FIXME: However, if this is seen and EVPD C0
* indicates that this is due to a NDU in
* progress, we should set FAIL_PATH too.
* This indicates we might have to do a SCSI
* inquiry in the end_io path. Ugh.
*
* Can return FAILED only when we want the error
* recovery process to kick in.
*/
return SUCCESS;
break;
case ILLEGAL_REQUEST:
if (sense_hdr->asc == 0x25 && sense_hdr->ascq == 0x01)
/*
* An array based copy is in progress. Do not
* fail the path, do not bypass to another PG,
* do not retry. Fail the IO immediately.
* (Actually this is the same conclusion as in
* the default handler, but lets make sure.)
*
* Can return FAILED only when we want the error
* recovery process to kick in.
*/
return SUCCESS;
break;
case UNIT_ATTENTION:
if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00)
/*
* Unit Attention Code. This is the first IO
* to the new path, so just retry.
*/
return NEEDS_RETRY;
break;
}
/* success just means we do not care what scsi-ml does */
return SUCCESS;
}
const struct scsi_dh_devlist clariion_dev_list[] = {
{"DGC", "RAID"},
{"DGC", "DISK"},
{NULL, NULL},
};
static int clariion_bus_attach(struct scsi_device *sdev);
static void clariion_bus_detach(struct scsi_device *sdev);
static struct scsi_device_handler clariion_dh = {
.name = CLARIION_NAME,
.module = THIS_MODULE,
.devlist = clariion_dev_list,
.attach = clariion_bus_attach,
.detach = clariion_bus_detach,
.check_sense = clariion_check_sense,
.activate = clariion_activate,
};
/*
* TODO: need some interface so we can set trespass values
*/
static int clariion_bus_attach(struct scsi_device *sdev)
{
struct scsi_dh_data *scsi_dh_data;
struct clariion_dh_data *h;
unsigned long flags;
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",
CLARIION_NAME);
return -ENOMEM;
}
scsi_dh_data->scsi_dh = &clariion_dh;
h = (struct clariion_dh_data *) scsi_dh_data->buf;
h->default_sp = CLARIION_UNBOUND_LU;
h->current_sp = CLARIION_UNBOUND_LU;
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, "Attached %s.\n", CLARIION_NAME);
try_module_get(THIS_MODULE);
return 0;
}
static void clariion_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);
sdev_printk(KERN_NOTICE, sdev, "Detached %s.\n",
CLARIION_NAME);
kfree(scsi_dh_data);
module_put(THIS_MODULE);
}
static int __init clariion_init(void)
{
int r;
r = scsi_register_device_handler(&clariion_dh);
if (r != 0)
printk(KERN_ERR "Failed to register scsi device handler.");
return r;
}
static void __exit clariion_exit(void)
{
scsi_unregister_device_handler(&clariion_dh);
}
module_init(clariion_init);
module_exit(clariion_exit);
MODULE_DESCRIPTION("EMC CX/AX/FC-family driver");
MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, Chandra Seetharaman <sekharan@us.ibm.com>");
MODULE_LICENSE("GPL");
