Andrew,
Attached is the patch that addresses all your comments except moving the
lock around blk_execute_rq_nowait(). Moving the lock ahead makes the
function to return more than one place (which is what I was trying to
avoid earlier). Let me now if you prefer it that way.
Thanks,
chandra
On Wed, 2007-07-11 at 14:43 -0700, Andrew Morton wrote:
--snip
> > + DMINFO("queueing MODE_SELECT command on %s", h->path->dev->name);
> > +
> > + blk_execute_rq_nowait(q, NULL, rq, 1, mode_select_endio);
>
> I suspect we could call this after dropping the lock?
>
> > + h->ctlr->submitted = 1;
> > + goto drop_lock;
> > +fail_path:
> > + dm_pg_init_complete(h->path, MP_FAIL_PATH);
> > +drop_lock:
> > + spin_unlock(&h->ctlr->lock);
> > +}
--snip--
-----------
From: Chandra Seetharaman <sekharan@xxxxxxxxxx>
This patch supports LSI/Engenio devices in RDAC mode. Like dm-emc
it requires userspace support. In your multipath.conf file you must have:
path_checker rdac
hardware_handler "1 rdac"
prio_callout "/sbin/mpath_prio_tpc /dev/%n"
And you also then must have a updated multipath tools release which
has rdac support.
--
Signed-off-by: Chandra Seetharaman <sekharan@xxxxxxxxxx>
Signed-off-by: Mike Christie <michaelc@xxxxxxxxxxx>
Signed-off-by: Alasdair G Kergon <agk@xxxxxxxxxx>
Index: linux-2.6.22/drivers/md/Kconfig
===================================================================
--- linux-2.6.22.orig/drivers/md/Kconfig
+++ linux-2.6.22/drivers/md/Kconfig
@@ -262,6 +262,12 @@ config DM_MULTIPATH_EMC
---help---
Multipath support for EMC CX/AX series hardware.
+config DM_MULTIPATH_RDAC
+ tristate "LSI/Engenio RDAC multipath support (EXPERIMENTAL)"
+ depends on DM_MULTIPATH && BLK_DEV_DM && EXPERIMENTAL
+ ---help---
+ Multipath support for LSI/Engenio RDAC.
+
config DM_DELAY
tristate "I/O delaying target (EXPERIMENTAL)"
depends on BLK_DEV_DM && EXPERIMENTAL
Index: linux-2.6.22/drivers/md/Makefile
===================================================================
--- linux-2.6.22.orig/drivers/md/Makefile
+++ linux-2.6.22/drivers/md/Makefile
@@ -7,6 +7,7 @@ dm-mod-objs := dm.o dm-table.o dm-target
dm-multipath-objs := dm-hw-handler.o dm-path-selector.o dm-mpath.o
dm-snapshot-objs := dm-snap.o dm-exception-store.o
dm-mirror-objs := dm-log.o dm-raid1.o
+dm-rdac-objs := dm-mpath-rdac.o
md-mod-objs := md.o bitmap.o
raid456-objs := raid5.o raid6algos.o raid6recov.o raid6tables.o \
raid6int1.o raid6int2.o raid6int4.o \
@@ -34,6 +35,7 @@ obj-$(CONFIG_DM_CRYPT) += dm-crypt.o
obj-$(CONFIG_DM_DELAY) += dm-delay.o
obj-$(CONFIG_DM_MULTIPATH) += dm-multipath.o dm-round-robin.o
obj-$(CONFIG_DM_MULTIPATH_EMC) += dm-emc.o
+obj-$(CONFIG_DM_MULTIPATH_RDAC) += dm-rdac.o
obj-$(CONFIG_DM_SNAPSHOT) += dm-snapshot.o
obj-$(CONFIG_DM_MIRROR) += dm-mirror.o
obj-$(CONFIG_DM_ZERO) += dm-zero.o
Index: linux-2.6.22/drivers/md/dm-mpath-rdac.c
===================================================================
--- /dev/null
+++ linux-2.6.22/drivers/md/dm-mpath-rdac.c
@@ -0,0 +1,700 @@
+/*
+ * Engenio/LSI RDAC DM HW 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_cmnd.h>
+#include <scsi/scsi_eh.h>
+
+#define DM_MSG_PREFIX "multipath rdac"
+
+#include "dm.h"
+#include "dm-hw-handler.h"
+
+#define RDAC_DM_HWH_NAME "rdac"
+#define RDAC_DM_HWH_VER "0.4"
+
+/*
+ * 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_ALL_LUNS 0x01
+#define RDAC_MODE_TRANSFER_SPECIFIED_LUNS 0x02
+
+/*
+ * RDAC Options field
+ */
+#define RDAC_FORCED_QUIESENCE 0x02
+
+#define RDAC_FAILOVER_TIMEOUT (60 * HZ)
+
+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_10_ms;
+ struct kref kref;
+ struct list_head node; /* list of all controllers */
+ spinlock_t lock;
+ int submitted;
+ struct list_head cmd_list; /* list of commands to be submitted */
+ 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_handler {
+ struct list_head entry; /* list waiting to submit MODE SELECT */
+ unsigned timeout;
+ struct rdac_controller *ctlr;
+#define UNINITIALIZED_LUN (1 << 8)
+ unsigned lun;
+ unsigned char sense[SCSI_SENSE_BUFFERSIZE];
+ struct dm_path *path;
+ struct work_struct work;
+#define SEND_C2_INQUIRY 1
+#define SEND_C4_INQUIRY 2
+#define SEND_C8_INQUIRY 3
+#define SEND_C9_INQUIRY 4
+#define SEND_MODE_SELECT 5
+ int cmd_to_send;
+ 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 struct workqueue_struct *rdac_wkqd;
+
+static inline int had_failures(struct request *req, int error)
+{
+ return (error || host_byte(req->errors) != DID_OK ||
+ msg_byte(req->errors) != COMMAND_COMPLETE);
+}
+
+static void rdac_resubmit_all(struct rdac_handler *h)
+{
+ struct rdac_controller *ctlr = h->ctlr;
+ struct rdac_handler *tmp, *h1;
+
+ spin_lock(&ctlr->lock);
+ list_for_each_entry_safe(h1, tmp, &ctlr->cmd_list, entry) {
+ h1->cmd_to_send = SEND_C9_INQUIRY;
+ queue_work(rdac_wkqd, &h1->work);
+ list_del(&h1->entry);
+ }
+ ctlr->submitted = 0;
+ spin_unlock(&ctlr->lock);
+}
+
+static void mode_select_endio(struct request *req, int error)
+{
+ struct rdac_handler *h = req->end_io_data;
+ struct scsi_sense_hdr sense_hdr;
+ int sense = 0, fail = 0;
+
+ if (had_failures(req, error)) {
+ fail = 1;
+ goto failed;
+ }
+
+ if (status_byte(req->errors) == CHECK_CONDITION) {
+ scsi_normalize_sense(req->sense, SCSI_SENSE_BUFFERSIZE,
+ &sense_hdr);
+ 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
+ */
+ h->cmd_to_send = SEND_C9_INQUIRY;
+ queue_work(rdac_wkqd, &h->work);
+ goto done;
+ }
+ if (sense)
+ DMINFO("MODE_SELECT failed on %s with sense 0x%x",
+ h->path->dev->name, sense);
+ }
+failed:
+ if (fail || sense)
+ dm_pg_init_complete(h->path, MP_FAIL_PATH);
+ else
+ dm_pg_init_complete(h->path, 0);
+
+done:
+ rdac_resubmit_all(h);
+ __blk_put_request(req->q, req);
+}
+
+static struct request *get_rdac_req(struct rdac_handler *h,
+ void *buffer, unsigned buflen, int rw)
+{
+ struct request *rq;
+ struct request_queue *q = bdev_get_queue(h->path->dev->bdev);
+
+ rq = blk_get_request(q, rw, GFP_KERNEL);
+
+ if (!rq) {
+ DMINFO("get_rdac_req: blk_get_request failed");
+ return NULL;
+ }
+
+ if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_KERNEL)) {
+ blk_put_request(rq);
+ DMINFO("get_rdac_req: blk_rq_map_kern failed");
+ 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->end_io_data = h;
+ rq->timeout = h->timeout;
+ rq->cmd_type = REQ_TYPE_BLOCK_PC;
+ rq->cmd_flags = REQ_FAILFAST | REQ_NOMERGE;
+ return rq;
+}
+
+static struct request *rdac_failover_get(struct rdac_handler *h)
+{
+ struct request *rq;
+ struct rdac_mode_common *common;
+ unsigned data_size;
+
+ if (h->ctlr->use_10_ms) {
+ 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(h, &h->ctlr->mode_select, data_size, WRITE);
+ if (!rq) {
+ DMERR("rdac_failover_get: no rq");
+ return NULL;
+ }
+
+ /* Prepare the command. */
+ if (h->ctlr->use_10_ms) {
+ 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;
+}
+
+/* Acquires h->ctlr->lock */
+static void submit_mode_select(struct rdac_handler *h)
+{
+ struct request *rq;
+ struct request_queue *q = bdev_get_queue(h->path->dev->bdev);
+
+ spin_lock(&h->ctlr->lock);
+ if (h->ctlr->submitted) {
+ list_add(&h->entry, &h->ctlr->cmd_list);
+ goto drop_lock;
+ }
+
+ if (!q) {
+ DMINFO("submit_mode_select: no queue");
+ goto fail_path;
+ }
+
+ rq = rdac_failover_get(h);
+ if (!rq) {
+ DMERR("submit_mode_select: no rq");
+ goto fail_path;
+ }
+
+ DMINFO("queueing MODE_SELECT command on %s", h->path->dev->name);
+
+ blk_execute_rq_nowait(q, NULL, rq, 1, mode_select_endio);
+ h->ctlr->submitted = 1;
+ goto drop_lock;
+fail_path:
+ dm_pg_init_complete(h->path, MP_FAIL_PATH);
+drop_lock:
+ spin_unlock(&h->ctlr->lock);
+}
+
+static void release_ctlr(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);
+ spin_lock_init(&ctlr->lock);
+ ctlr->submitted = 0;
+ ctlr->use_10_ms = -1;
+ INIT_LIST_HEAD(&ctlr->cmd_list);
+ list_add(&ctlr->node, &ctlr_list);
+done:
+ spin_unlock(&list_lock);
+ return ctlr;
+}
+
+static void c4_endio(struct request *req, int error)
+{
+ struct rdac_handler *h = req->end_io_data;
+ struct c4_inquiry *sp;
+
+ if (had_failures(req, error)) {
+ dm_pg_init_complete(h->path, MP_FAIL_PATH);
+ goto done;
+ }
+
+ sp = &h->inq.c4;
+
+ h->ctlr = get_controller(sp->subsys_id, sp->slot_id);
+
+ if (h->ctlr) {
+ h->cmd_to_send = SEND_C9_INQUIRY;
+ queue_work(rdac_wkqd, &h->work);
+ } else
+ dm_pg_init_complete(h->path, MP_FAIL_PATH);
+done:
+ __blk_put_request(req->q, req);
+}
+
+static void c2_endio(struct request *req, int error)
+{
+ struct rdac_handler *h = req->end_io_data;
+ struct c2_inquiry *sp;
+
+ if (had_failures(req, error)) {
+ dm_pg_init_complete(h->path, MP_FAIL_PATH);
+ goto done;
+ }
+
+ sp = &h->inq.c2;
+
+ /* If more than MODE6_MAX_LUN luns are supported, use mode select 10 */
+ if (sp->max_lun_supported >= MODE6_MAX_LUN)
+ h->ctlr->use_10_ms = 1;
+ else
+ h->ctlr->use_10_ms = 0;
+
+ h->cmd_to_send = SEND_MODE_SELECT;
+ queue_work(rdac_wkqd, &h->work);
+done:
+ __blk_put_request(req->q, req);
+}
+
+static void c9_endio(struct request *req, int error)
+{
+ struct rdac_handler *h = req->end_io_data;
+ struct c9_inquiry *sp;
+
+ if (had_failures(req, error)) {
+ dm_pg_init_complete(h->path, MP_FAIL_PATH);
+ goto done;
+ }
+
+ /* We need to look at the sense keys here to take clear action.
+ * For now simple logic: If the host is in AVT mode or if controller
+ * owns the lun, return dm_pg_init_complete(), otherwise submit
+ * MODE SELECT.
+ */
+ sp = &h->inq.c9;
+
+ /* If in AVT mode, return success */
+ if ((sp->avte_cvp >> 7) == 0x1) {
+ dm_pg_init_complete(h->path, 0);
+ goto done;
+ }
+
+ /* If the controller on this path owns the LUN, return success */
+ if (sp->avte_cvp & 0x1) {
+ dm_pg_init_complete(h->path, 0);
+ goto done;
+ }
+
+ if (h->ctlr) {
+ if (h->ctlr->use_10_ms == -1)
+ h->cmd_to_send = SEND_C2_INQUIRY;
+ else
+ h->cmd_to_send = SEND_MODE_SELECT;
+ } else
+ h->cmd_to_send = SEND_C4_INQUIRY;
+ queue_work(rdac_wkqd, &h->work);
+done:
+ __blk_put_request(req->q, req);
+}
+
+static void c8_endio(struct request *req, int error)
+{
+ struct rdac_handler *h = req->end_io_data;
+ struct c8_inquiry *sp;
+
+ if (had_failures(req, error)) {
+ dm_pg_init_complete(h->path, MP_FAIL_PATH);
+ goto done;
+ }
+
+ /* We need to look at the sense keys here to take clear action.
+ * For now simple logic: Get the lun from the inquiry page.
+ */
+ sp = &h->inq.c8;
+ h->lun = sp->lun[7]; /* currently it uses only one byte */
+ h->cmd_to_send = SEND_C9_INQUIRY;
+ queue_work(rdac_wkqd, &h->work);
+done:
+ __blk_put_request(req->q, req);
+}
+
+static void submit_inquiry(struct rdac_handler *h, int page_code,
+ unsigned int len, rq_end_io_fn endio)
+{
+ struct request *rq;
+ struct request_queue *q = bdev_get_queue(h->path->dev->bdev);
+
+ if (!q)
+ goto fail_path;
+
+ rq = get_rdac_req(h, &h->inq, len, READ);
+ if (!rq)
+ goto fail_path;
+
+ /* 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);
+ blk_execute_rq_nowait(q, NULL, rq, 1, endio);
+ return;
+
+fail_path:
+ dm_pg_init_complete(h->path, MP_FAIL_PATH);
+}
+
+static void service_wkq(struct work_struct *work)
+{
+ struct rdac_handler *h = container_of(work, struct rdac_handler, work);
+
+ switch (h->cmd_to_send) {
+ case SEND_C2_INQUIRY:
+ submit_inquiry(h, 0xC2, sizeof(struct c2_inquiry), c2_endio);
+ break;
+ case SEND_C4_INQUIRY:
+ submit_inquiry(h, 0xC4, sizeof(struct c4_inquiry), c4_endio);
+ break;
+ case SEND_C8_INQUIRY:
+ submit_inquiry(h, 0xC8, sizeof(struct c8_inquiry), c8_endio);
+ break;
+ case SEND_C9_INQUIRY:
+ submit_inquiry(h, 0xC9, sizeof(struct c9_inquiry), c9_endio);
+ break;
+ case SEND_MODE_SELECT:
+ submit_mode_select(h);
+ break;
+ default:
+ BUG();
+ }
+}
+/*
+ * only support subpage2c until we confirm that this is just a matter of
+ * of updating firmware or not, and RDAC (basic AVT works already) for now
+ * but we can add these in in when we get time and testers
+ */
+static int rdac_create(struct hw_handler *hwh, unsigned argc, char **argv)
+{
+ struct rdac_handler *h;
+ unsigned timeout;
+
+ if (argc == 0) {
+ /* No arguments: use defaults */
+ timeout = RDAC_FAILOVER_TIMEOUT;
+ } else if (argc != 1) {
+ DMWARN("incorrect number of arguments");
+ return -EINVAL;
+ } else {
+ if (sscanf(argv[1], "%u", &timeout) != 1) {
+ DMWARN("invalid timeout value");
+ return -EINVAL;
+ }
+ }
+
+ h = kzalloc(sizeof(*h), GFP_KERNEL);
+ if (!h)
+ return -ENOMEM;
+
+ hwh->context = h;
+ h->timeout = timeout;
+ h->lun = UNINITIALIZED_LUN;
+ INIT_WORK(&h->work, service_wkq);
+ DMWARN("using RDAC command with timeout %u", h->timeout);
+
+ return 0;
+}
+
+static void rdac_destroy(struct hw_handler *hwh)
+{
+ struct rdac_handler *h = hwh->context;
+
+ if (h->ctlr)
+ kref_put(&h->ctlr->kref, release_ctlr);
+ kfree(h);
+ hwh->context = NULL;
+}
+
+static unsigned rdac_error(struct hw_handler *hwh, struct bio *bio)
+{
+ /* Try default handler */
+ return dm_scsi_err_handler(hwh, bio);
+}
+
+static void rdac_pg_init(struct hw_handler *hwh, unsigned bypassed,
+ struct dm_path *path)
+{
+ struct rdac_handler *h = hwh->context;
+
+ h->path = path;
+ switch (h->lun) {
+ case UNINITIALIZED_LUN:
+ submit_inquiry(h, 0xC8, sizeof(struct c8_inquiry), c8_endio);
+ break;
+ default:
+ submit_inquiry(h, 0xC9, sizeof(struct c9_inquiry), c9_endio);
+ }
+}
+
+static struct hw_handler_type rdac_handler = {
+ .name = RDAC_DM_HWH_NAME,
+ .module = THIS_MODULE,
+ .create = rdac_create,
+ .destroy = rdac_destroy,
+ .pg_init = rdac_pg_init,
+ .error = rdac_error,
+};
+
+static int __init rdac_init(void)
+{
+ int r = dm_register_hw_handler(&rdac_handler);
+
+ if (r < 0) {
+ DMERR("%s: register failed %d", RDAC_DM_HWH_NAME, r);
+ return r;
+ }
+
+ rdac_wkqd = create_singlethread_workqueue("rdac_wkqd");
+ if (!rdac_wkqd) {
+ DMERR("Failed to create workqueue rdac_wkqd.");
+ dm_unregister_hw_handler(&rdac_handler);
+ return -ENOMEM;
+ }
+
+ DMINFO("%s: version %s loaded", RDAC_DM_HWH_NAME, RDAC_DM_HWH_VER);
+ return 0;
+}
+
+static void __exit rdac_exit(void)
+{
+ int r = dm_unregister_hw_handler(&rdac_handler);
+
+ destroy_workqueue(rdac_wkqd);
+ if (r < 0)
+ DMERR("%s: unregister failed %d", RDAC_DM_HWH_NAME, r);
+}
+
+module_init(rdac_init);
+module_exit(rdac_exit);
+
+MODULE_DESCRIPTION("DM Multipath LSI/Engenio RDAC support");
+MODULE_AUTHOR("Mike Christie, Chandra Seetharaman");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(RDAC_DM_HWH_VER);
--
----------------------------------------------------------------------
Chandra Seetharaman | Be careful what you choose....
- sekharan@xxxxxxxxxx | .......you may get it.
----------------------------------------------------------------------
--
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