linux-stable/drivers/scsi/device_handler/scsi_dh_emc.c
Mike Christie 6000a368cd [SCSI] block: separate failfast into multiple bits.
Multipath is best at handling transport errors. If it gets a device
error then there is not much the multipath layer can do. It will just
access the same device but from a different path.

This patch breaks up failfast into device, transport and driver errors.
The multipath layers (md and dm mutlipath) only ask the lower levels to
fast fail transport errors. The user of failfast, read ahead, will ask
to fast fail on all errors.

Note that blk_noretry_request will return true if any failfast bit
is set. This allows drivers that do not support the multipath failfast
bits to continue to fail on any failfast error like before. Drivers
like scsi that are able to fail fast specific errors can check
for the specific fail fast type. In the next patch I will convert
scsi.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-10-13 09:28:52 -04:00

678 lines
17 KiB
C

/*
* 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"
#define CLARIION_TRESPASS_PAGE 0x22
#define CLARIION_BUFFER_SIZE 0xFC
#define CLARIION_TIMEOUT (60 * HZ)
#define CLARIION_RETRIES 3
#define CLARIION_UNBOUND_LU -1
#define CLARIION_SP_A 0
#define CLARIION_SP_B 1
/* Flags */
#define CLARIION_SHORT_TRESPASS 1
#define CLARIION_HONOR_RESERVATIONS 2
/* LUN states */
#define CLARIION_LUN_UNINITIALIZED -1
#define CLARIION_LUN_UNBOUND 0
#define CLARIION_LUN_BOUND 1
#define CLARIION_LUN_OWNED 2
static unsigned char long_trespass[] = {
0, 0, 0, 0, 0, 0, 0, 0,
CLARIION_TRESPASS_PAGE, /* Page code */
0x09, /* Page length - 2 */
0x01, /* Trespass code */
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 */
0x01, /* Trespass code */
0xff, /* Trespass target */
};
static const char * lun_state[] =
{
"not bound",
"bound",
"owned",
};
struct clariion_dh_data {
/*
* Flags:
* CLARIION_SHORT_TRESPASS
* Use short trespass command (FC-series) or the long version
* (default for AX/CX CLARiiON arrays).
*
* CLARIION_HONOR_RESERVATIONS
* Whether or not (default) to honor SCSI reservations when
* initiating a switch-over.
*/
unsigned flags;
/*
* I/O buffer for both MODE_SELECT and INQUIRY commands.
*/
unsigned 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];
unsigned int senselen;
/*
* LUN state
*/
int lun_state;
/*
* SP Port number
*/
int port;
/*
* which SP (A=0,B=1,UNBOUND=-1) is the default SP for this
* path's mapped LUN
*/
int default_sp;
/*
* which SP (A=0,B=1,UNBOUND=-1) is the active SP for this
* path's mapped LUN
*/
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, char *sense)
{
int err = SCSI_DH_IO;
struct scsi_sense_hdr sshdr;
if (!scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)) {
sdev_printk(KERN_ERR, sdev, "%s: Found valid sense data 0x%2x, "
"0x%2x, 0x%2x while sending CLARiiON trespass "
"command.\n", CLARIION_NAME, 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, "%s: Array Based Copy in "
"progress while sending CLARiiON trespass "
"command.\n", CLARIION_NAME);
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, "%s: Detected in-progress "
"ucode upgrade NDU operation while sending "
"CLARiiON trespass command.\n", CLARIION_NAME);
err = SCSI_DH_DEV_TEMP_BUSY;
} else
err = SCSI_DH_DEV_FAILED;
} else {
sdev_printk(KERN_INFO, sdev,
"%s: failed to send MODE SELECT, no sense available\n",
CLARIION_NAME);
}
return err;
}
static int parse_sp_info_reply(struct scsi_device *sdev,
struct clariion_dh_data *csdev)
{
int err = SCSI_DH_OK;
/* check for in-progress ucode upgrade (NDU) */
if (csdev->buffer[48] != 0) {
sdev_printk(KERN_NOTICE, sdev, "%s: Detected in-progress "
"ucode upgrade NDU operation while finding "
"current active SP.", CLARIION_NAME);
err = SCSI_DH_DEV_TEMP_BUSY;
goto out;
}
if (csdev->buffer[4] > 2) {
/* Invalid buffer format */
sdev_printk(KERN_NOTICE, sdev,
"%s: invalid VPD page 0xC0 format\n",
CLARIION_NAME);
err = SCSI_DH_NOSYS;
goto out;
}
switch (csdev->buffer[28] & 0x0f) {
case 6:
sdev_printk(KERN_NOTICE, sdev,
"%s: ALUA failover mode detected\n",
CLARIION_NAME);
break;
case 4:
/* Linux failover */
break;
default:
sdev_printk(KERN_WARNING, sdev,
"%s: Invalid failover mode %d\n",
CLARIION_NAME, csdev->buffer[28] & 0x0f);
err = SCSI_DH_NOSYS;
goto out;
}
csdev->default_sp = csdev->buffer[5];
csdev->lun_state = csdev->buffer[4];
csdev->current_sp = csdev->buffer[8];
csdev->port = csdev->buffer[7];
out:
return err;
}
#define emc_default_str "FC (Legacy)"
static char * parse_sp_model(struct scsi_device *sdev, unsigned char *buffer)
{
unsigned char len = buffer[4] + 5;
char *sp_model = NULL;
unsigned char sp_len, serial_len;
if (len < 160) {
sdev_printk(KERN_WARNING, sdev,
"%s: Invalid information section length %d\n",
CLARIION_NAME, len);
/* Check for old FC arrays */
if (!strncmp(buffer + 8, "DGC", 3)) {
/* Old FC array, not supporting extended information */
sp_model = emc_default_str;
}
goto out;
}
/*
* Parse extended information for SP model number
*/
serial_len = buffer[160];
if (serial_len == 0 || serial_len + 161 > len) {
sdev_printk(KERN_WARNING, sdev,
"%s: Invalid array serial number length %d\n",
CLARIION_NAME, serial_len);
goto out;
}
sp_len = buffer[99];
if (sp_len == 0 || serial_len + sp_len + 161 > len) {
sdev_printk(KERN_WARNING, sdev,
"%s: Invalid model number length %d\n",
CLARIION_NAME, sp_len);
goto out;
}
sp_model = &buffer[serial_len + 161];
/* Strip whitespace at the end */
while (sp_len > 1 && sp_model[sp_len - 1] == ' ')
sp_len--;
sp_model[sp_len] = '\0';
out:
return sp_model;
}
/*
* 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,
unsigned char *buffer)
{
struct request *rq;
int len = 0;
rq = blk_get_request(sdev->request_queue,
(cmd == MODE_SELECT) ? WRITE : READ, GFP_NOIO);
if (!rq) {
sdev_printk(KERN_INFO, sdev, "get_req: blk_get_request failed");
return NULL;
}
rq->cmd_len = COMMAND_SIZE(cmd);
rq->cmd[0] = cmd;
switch (cmd) {
case MODE_SELECT:
len = sizeof(short_trespass);
rq->cmd_flags |= REQ_RW;
rq->cmd[1] = 0x10;
break;
case MODE_SELECT_10:
len = sizeof(long_trespass);
rq->cmd_flags |= REQ_RW;
rq->cmd[1] = 0x10;
break;
case INQUIRY:
len = CLARIION_BUFFER_SIZE;
memset(buffer, 0, len);
break;
default:
BUG_ON(1);
break;
}
rq->cmd[4] = len;
rq->cmd_type = REQ_TYPE_BLOCK_PC;
rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
REQ_FAILFAST_DRIVER;
rq->timeout = CLARIION_TIMEOUT;
rq->retries = CLARIION_RETRIES;
if (blk_rq_map_kern(rq->q, rq, buffer, len, GFP_NOIO)) {
blk_put_request(rq);
return NULL;
}
return rq;
}
static int send_inquiry_cmd(struct scsi_device *sdev, int page,
struct clariion_dh_data *csdev)
{
struct request *rq = get_req(sdev, INQUIRY, csdev->buffer);
int err;
if (!rq)
return SCSI_DH_RES_TEMP_UNAVAIL;
rq->sense = csdev->sense;
memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
rq->sense_len = csdev->senselen = 0;
rq->cmd[0] = INQUIRY;
if (page != 0) {
rq->cmd[1] = 1;
rq->cmd[2] = page;
}
err = blk_execute_rq(sdev->request_queue, NULL, rq, 1);
if (err == -EIO) {
sdev_printk(KERN_INFO, sdev,
"%s: failed to send %s INQUIRY: %x\n",
CLARIION_NAME, page?"EVPD":"standard",
rq->errors);
csdev->senselen = rq->sense_len;
err = SCSI_DH_IO;
}
blk_put_request(rq);
return err;
}
static int send_trespass_cmd(struct scsi_device *sdev,
struct clariion_dh_data *csdev)
{
struct request *rq;
unsigned char *page22;
int err, len, cmd;
if (csdev->flags & CLARIION_SHORT_TRESPASS) {
page22 = short_trespass;
if (!(csdev->flags & CLARIION_HONOR_RESERVATIONS))
/* Set Honor Reservations bit */
page22[6] |= 0x80;
len = sizeof(short_trespass);
cmd = MODE_SELECT;
} else {
page22 = long_trespass;
if (!(csdev->flags & CLARIION_HONOR_RESERVATIONS))
/* Set Honor Reservations bit */
page22[10] |= 0x80;
len = sizeof(long_trespass);
cmd = MODE_SELECT_10;
}
BUG_ON((len > CLARIION_BUFFER_SIZE));
memcpy(csdev->buffer, page22, len);
rq = get_req(sdev, cmd, csdev->buffer);
if (!rq)
return SCSI_DH_RES_TEMP_UNAVAIL;
rq->sense = csdev->sense;
memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
rq->sense_len = csdev->senselen = 0;
err = blk_execute_rq(sdev->request_queue, NULL, rq, 1);
if (err == -EIO) {
if (rq->sense_len) {
err = trespass_endio(sdev, csdev->sense);
} else {
sdev_printk(KERN_INFO, sdev,
"%s: failed to send MODE SELECT: %x\n",
CLARIION_NAME, rq->errors);
}
}
blk_put_request(rq);
return err;
}
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 ADD_TO_MLQUEUE;
break;
}
return SCSI_RETURN_NOT_HANDLED;
}
static int clariion_prep_fn(struct scsi_device *sdev, struct request *req)
{
struct clariion_dh_data *h = get_clariion_data(sdev);
int ret = BLKPREP_OK;
if (h->lun_state != CLARIION_LUN_OWNED) {
ret = BLKPREP_KILL;
req->cmd_flags |= REQ_QUIET;
}
return ret;
}
static int clariion_std_inquiry(struct scsi_device *sdev,
struct clariion_dh_data *csdev)
{
int err;
char *sp_model;
err = send_inquiry_cmd(sdev, 0, csdev);
if (err != SCSI_DH_OK && csdev->senselen) {
struct scsi_sense_hdr sshdr;
if (scsi_normalize_sense(csdev->sense, SCSI_SENSE_BUFFERSIZE,
&sshdr)) {
sdev_printk(KERN_ERR, sdev, "%s: INQUIRY sense code "
"%02x/%02x/%02x\n", CLARIION_NAME,
sshdr.sense_key, sshdr.asc, sshdr.ascq);
}
err = SCSI_DH_IO;
goto out;
}
sp_model = parse_sp_model(sdev, csdev->buffer);
if (!sp_model) {
err = SCSI_DH_DEV_UNSUPP;
goto out;
}
/*
* FC Series arrays do not support long trespass
*/
if (!strlen(sp_model) || !strncmp(sp_model, "FC",2))
csdev->flags |= CLARIION_SHORT_TRESPASS;
sdev_printk(KERN_INFO, sdev,
"%s: detected Clariion %s, flags %x\n",
CLARIION_NAME, sp_model, csdev->flags);
out:
return err;
}
static int clariion_send_inquiry(struct scsi_device *sdev,
struct clariion_dh_data *csdev)
{
int err, retry = CLARIION_RETRIES;
retry:
err = send_inquiry_cmd(sdev, 0xC0, csdev);
if (err != SCSI_DH_OK && csdev->senselen) {
struct scsi_sense_hdr sshdr;
err = scsi_normalize_sense(csdev->sense, SCSI_SENSE_BUFFERSIZE,
&sshdr);
if (!err)
return SCSI_DH_IO;
err = clariion_check_sense(sdev, &sshdr);
if (retry > 0 && err == ADD_TO_MLQUEUE) {
retry--;
goto retry;
}
sdev_printk(KERN_ERR, sdev, "%s: INQUIRY sense code "
"%02x/%02x/%02x\n", CLARIION_NAME,
sshdr.sense_key, sshdr.asc, sshdr.ascq);
err = SCSI_DH_IO;
} else {
err = parse_sp_info_reply(sdev, csdev);
}
return err;
}
static int clariion_activate(struct scsi_device *sdev)
{
struct clariion_dh_data *csdev = get_clariion_data(sdev);
int result;
result = clariion_send_inquiry(sdev, csdev);
if (result != SCSI_DH_OK)
goto done;
if (csdev->lun_state == CLARIION_LUN_OWNED)
goto done;
result = send_trespass_cmd(sdev, csdev);
if (result != SCSI_DH_OK)
goto done;
sdev_printk(KERN_INFO, sdev,"%s: %s trespass command sent\n",
CLARIION_NAME,
csdev->flags&CLARIION_SHORT_TRESPASS?"short":"long" );
/* Update status */
result = clariion_send_inquiry(sdev, csdev);
if (result != SCSI_DH_OK)
goto done;
done:
sdev_printk(KERN_INFO, sdev,
"%s: at SP %c Port %d (%s, default SP %c)\n",
CLARIION_NAME, csdev->current_sp + 'A',
csdev->port, lun_state[csdev->lun_state],
csdev->default_sp + 'A');
return result;
}
static const struct scsi_dh_devlist clariion_dev_list[] = {
{"DGC", "RAID"},
{"DGC", "DISK"},
{"DGC", "VRAID"},
{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,
.prep_fn = clariion_prep_fn,
};
/*
* 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;
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",
CLARIION_NAME);
return -ENOMEM;
}
scsi_dh_data->scsi_dh = &clariion_dh;
h = (struct clariion_dh_data *) scsi_dh_data->buf;
h->lun_state = CLARIION_LUN_UNINITIALIZED;
h->default_sp = CLARIION_UNBOUND_LU;
h->current_sp = CLARIION_UNBOUND_LU;
err = clariion_std_inquiry(sdev, h);
if (err != SCSI_DH_OK)
goto failed;
err = clariion_send_inquiry(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_INFO, sdev,
"%s: connected to SP %c Port %d (%s, default SP %c)\n",
CLARIION_NAME, h->current_sp + 'A',
h->port, lun_state[h->lun_state],
h->default_sp + 'A');
return 0;
failed:
kfree(scsi_dh_data);
sdev_printk(KERN_ERR, sdev, "%s: not attached\n",
CLARIION_NAME);
return -EINVAL;
}
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, "%s: Detached\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 "%s: Failed to register scsi device handler.",
CLARIION_NAME);
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");