diff options
Diffstat (limited to 'drivers/scsi/device_handler/scsi_dh_rdac.c')
-rw-r--r-- | drivers/scsi/device_handler/scsi_dh_rdac.c | 837 |
1 files changed, 837 insertions, 0 deletions
diff --git a/drivers/scsi/device_handler/scsi_dh_rdac.c b/drivers/scsi/device_handler/scsi_dh_rdac.c new file mode 100644 index 0000000000..c553864505 --- /dev/null +++ b/drivers/scsi/device_handler/scsi_dh_rdac.c @@ -0,0 +1,837 @@ +/* + * LSI/Engenio/NetApp E-Series 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> +#include <linux/workqueue.h> +#include <linux/slab.h> +#include <linux/module.h> + +#define RDAC_NAME "rdac" +#define RDAC_RETRY_COUNT 5 + +/* + * 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 +#define ARRAY_LABEL_LEN 31 + +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]; +}; + +#define UNIQUE_ID_LEN 16 +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[UNIQUE_ID_LEN]; + u8 array_user_label_len; + u8 array_user_label[60]; + u8 lun[8]; +}; + +struct rdac_controller { + u8 array_id[UNIQUE_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; + u8 index; + u8 array_name[ARRAY_LABEL_LEN]; + struct Scsi_Host *host; + spinlock_t ms_lock; + int ms_queued; + struct work_struct ms_work; + struct scsi_device *ms_sdev; + struct list_head ms_head; + struct list_head dh_list; +}; + +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 list_head node; + struct rdac_controller *ctlr; + struct scsi_device *sdev; +#define UNINITIALIZED_LUN (1 << 8) + unsigned lun; + +#define RDAC_MODE 0 +#define RDAC_MODE_AVT 1 +#define RDAC_MODE_IOSHIP 2 + unsigned char mode; + +#define RDAC_STATE_ACTIVE 0 +#define RDAC_STATE_PASSIVE 1 + unsigned char state; + +#define RDAC_LUN_UNOWNED 0 +#define RDAC_LUN_OWNED 1 + char lun_state; + +#define RDAC_PREFERRED 0 +#define RDAC_NON_PREFERRED 1 + char preferred; + + union { + struct c2_inquiry c2; + struct c4_inquiry c4; + struct c8_inquiry c8; + struct c9_inquiry c9; + } inq; +}; + +static const char *mode[] = { + "RDAC", + "AVT", + "IOSHIP", +}; +static const char *lun_state[] = +{ + "unowned", + "owned", +}; + +struct rdac_queue_data { + struct list_head entry; + struct rdac_dh_data *h; + activate_complete callback_fn; + void *callback_data; +}; + +static LIST_HEAD(ctlr_list); +static DEFINE_SPINLOCK(list_lock); +static struct workqueue_struct *kmpath_rdacd; +static void send_mode_select(struct work_struct *work); + +/* + * module parameter to enable rdac debug logging. + * 2 bits for each type of logging, only two types defined for now + * Can be enhanced if required at later point + */ +static int rdac_logging = 1; +module_param(rdac_logging, int, S_IRUGO|S_IWUSR); +MODULE_PARM_DESC(rdac_logging, "A bit mask of rdac logging levels, " + "Default is 1 - failover logging enabled, " + "set it to 0xF to enable all the logs"); + +#define RDAC_LOG_FAILOVER 0 +#define RDAC_LOG_SENSE 2 + +#define RDAC_LOG_BITS 2 + +#define RDAC_LOG_LEVEL(SHIFT) \ + ((rdac_logging >> (SHIFT)) & ((1 << (RDAC_LOG_BITS)) - 1)) + +#define RDAC_LOG(SHIFT, sdev, f, arg...) \ +do { \ + if (unlikely(RDAC_LOG_LEVEL(SHIFT))) \ + sdev_printk(KERN_INFO, sdev, RDAC_NAME ": " f "\n", ## arg); \ +} while (0); + +static unsigned int rdac_failover_get(struct rdac_controller *ctlr, + struct list_head *list, + unsigned char *cdb) +{ + struct rdac_mode_common *common; + unsigned data_size; + struct rdac_queue_data *qdata; + u8 *lun_table; + + if (ctlr->use_ms10) { + struct rdac_pg_expanded *rdac_pg; + + data_size = sizeof(struct rdac_pg_expanded); + rdac_pg = &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; + lun_table = rdac_pg->lun_table; + } else { + struct rdac_pg_legacy *rdac_pg; + + data_size = sizeof(struct rdac_pg_legacy); + rdac_pg = &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; + lun_table = rdac_pg->lun_table; + } + common->rdac_mode[1] = RDAC_MODE_TRANSFER_SPECIFIED_LUNS; + common->quiescence_timeout = RDAC_QUIESCENCE_TIME; + common->rdac_options = RDAC_FORCED_QUIESENCE; + + list_for_each_entry(qdata, list, entry) { + lun_table[qdata->h->lun] = 0x81; + } + + /* Prepare the command. */ + if (ctlr->use_ms10) { + cdb[0] = MODE_SELECT_10; + cdb[7] = data_size >> 8; + cdb[8] = data_size & 0xff; + } else { + cdb[0] = MODE_SELECT; + cdb[4] = data_size; + } + + return data_size; +} + +static void release_controller(struct kref *kref) +{ + struct rdac_controller *ctlr; + ctlr = container_of(kref, struct rdac_controller, kref); + + list_del(&ctlr->node); + kfree(ctlr); +} + +static struct rdac_controller *get_controller(int index, char *array_name, + u8 *array_id, struct scsi_device *sdev) +{ + struct rdac_controller *ctlr, *tmp; + + list_for_each_entry(tmp, &ctlr_list, node) { + if ((memcmp(tmp->array_id, array_id, UNIQUE_ID_LEN) == 0) && + (tmp->index == index) && + (tmp->host == sdev->host)) { + kref_get(&tmp->kref); + return tmp; + } + } + ctlr = kmalloc(sizeof(*ctlr), GFP_ATOMIC); + if (!ctlr) + return NULL; + + /* initialize fields of controller */ + memcpy(ctlr->array_id, array_id, UNIQUE_ID_LEN); + ctlr->index = index; + ctlr->host = sdev->host; + memcpy(ctlr->array_name, array_name, ARRAY_LABEL_LEN); + + kref_init(&ctlr->kref); + ctlr->use_ms10 = -1; + ctlr->ms_queued = 0; + ctlr->ms_sdev = NULL; + spin_lock_init(&ctlr->ms_lock); + INIT_WORK(&ctlr->ms_work, send_mode_select); + INIT_LIST_HEAD(&ctlr->ms_head); + list_add(&ctlr->node, &ctlr_list); + INIT_LIST_HEAD(&ctlr->dh_list); + + return ctlr; +} + +static int get_lun_info(struct scsi_device *sdev, struct rdac_dh_data *h, + char *array_name, u8 *array_id) +{ + int err = SCSI_DH_IO, i; + struct c8_inquiry *inqp = &h->inq.c8; + + if (!scsi_get_vpd_page(sdev, 0xC8, (unsigned char *)inqp, + sizeof(struct c8_inquiry))) { + 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 */ + + for(i=0; i<ARRAY_LABEL_LEN-1; ++i) + *(array_name+i) = inqp->array_user_label[(2*i)+1]; + + *(array_name+ARRAY_LABEL_LEN-1) = '\0'; + memset(array_id, 0, UNIQUE_ID_LEN); + memcpy(array_id, inqp->array_unique_id, inqp->array_uniq_id_len); + err = SCSI_DH_OK; + } + return err; +} + +static int check_ownership(struct scsi_device *sdev, struct rdac_dh_data *h) +{ + int err = SCSI_DH_IO, access_state; + struct rdac_dh_data *tmp; + struct c9_inquiry *inqp = &h->inq.c9; + + h->state = RDAC_STATE_ACTIVE; + if (!scsi_get_vpd_page(sdev, 0xC9, (unsigned char *)inqp, + sizeof(struct c9_inquiry))) { + /* detect the operating mode */ + if ((inqp->avte_cvp >> 5) & 0x1) + h->mode = RDAC_MODE_IOSHIP; /* LUN in IOSHIP mode */ + else if (inqp->avte_cvp >> 7) + h->mode = RDAC_MODE_AVT; /* LUN in AVT mode */ + else + h->mode = RDAC_MODE; /* LUN in RDAC mode */ + + /* Update ownership */ + if (inqp->avte_cvp & 0x1) { + h->lun_state = RDAC_LUN_OWNED; + access_state = SCSI_ACCESS_STATE_OPTIMAL; + } else { + h->lun_state = RDAC_LUN_UNOWNED; + if (h->mode == RDAC_MODE) { + h->state = RDAC_STATE_PASSIVE; + access_state = SCSI_ACCESS_STATE_STANDBY; + } else + access_state = SCSI_ACCESS_STATE_ACTIVE; + } + + /* Update path prio*/ + if (inqp->path_prio & 0x1) { + h->preferred = RDAC_PREFERRED; + access_state |= SCSI_ACCESS_STATE_PREFERRED; + } else + h->preferred = RDAC_NON_PREFERRED; + rcu_read_lock(); + list_for_each_entry_rcu(tmp, &h->ctlr->dh_list, node) { + /* h->sdev should always be valid */ + BUG_ON(!tmp->sdev); + tmp->sdev->access_state = access_state; + } + rcu_read_unlock(); + err = SCSI_DH_OK; + } + + return err; +} + +static int initialize_controller(struct scsi_device *sdev, + struct rdac_dh_data *h, char *array_name, u8 *array_id) +{ + int err = SCSI_DH_IO, index; + struct c4_inquiry *inqp = &h->inq.c4; + + if (!scsi_get_vpd_page(sdev, 0xC4, (unsigned char *)inqp, + sizeof(struct c4_inquiry))) { + /* get the controller index */ + if (inqp->slot_id[1] == 0x31) + index = 0; + else + index = 1; + + spin_lock(&list_lock); + h->ctlr = get_controller(index, array_name, array_id, sdev); + if (!h->ctlr) + err = SCSI_DH_RES_TEMP_UNAVAIL; + else { + h->sdev = sdev; + list_add_rcu(&h->node, &h->ctlr->dh_list); + } + spin_unlock(&list_lock); + err = SCSI_DH_OK; + } + return err; +} + +static int set_mode_select(struct scsi_device *sdev, struct rdac_dh_data *h) +{ + int err = SCSI_DH_IO; + struct c2_inquiry *inqp = &h->inq.c2; + + if (!scsi_get_vpd_page(sdev, 0xC2, (unsigned char *)inqp, + sizeof(struct c2_inquiry))) { + /* + * 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; + err = SCSI_DH_OK; + } + return err; +} + +static int mode_select_handle_sense(struct scsi_device *sdev, + struct scsi_sense_hdr *sense_hdr) +{ + int err = SCSI_DH_IO; + struct rdac_dh_data *h = sdev->handler_data; + + if (!scsi_sense_valid(sense_hdr)) + goto done; + + switch (sense_hdr->sense_key) { + case NO_SENSE: + case ABORTED_COMMAND: + case UNIT_ATTENTION: + err = SCSI_DH_RETRY; + break; + case NOT_READY: + if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x01) + /* LUN Not Ready and is in the Process of Becoming + * Ready + */ + err = SCSI_DH_RETRY; + break; + case ILLEGAL_REQUEST: + if (sense_hdr->asc == 0x91 && sense_hdr->ascq == 0x36) + /* + * Command Lock contention + */ + err = SCSI_DH_IMM_RETRY; + break; + default: + break; + } + + RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, " + "MODE_SELECT returned with sense %02x/%02x/%02x", + (char *) h->ctlr->array_name, h->ctlr->index, + sense_hdr->sense_key, sense_hdr->asc, sense_hdr->ascq); + +done: + return err; +} + +static void send_mode_select(struct work_struct *work) +{ + struct rdac_controller *ctlr = + container_of(work, struct rdac_controller, ms_work); + struct scsi_device *sdev = ctlr->ms_sdev; + struct rdac_dh_data *h = sdev->handler_data; + int err = SCSI_DH_OK, retry_cnt = RDAC_RETRY_COUNT; + struct rdac_queue_data *tmp, *qdata; + LIST_HEAD(list); + unsigned char cdb[MAX_COMMAND_SIZE]; + struct scsi_sense_hdr sshdr; + unsigned int data_size; + blk_opf_t opf = REQ_OP_DRV_OUT | REQ_FAILFAST_DEV | + REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER; + const struct scsi_exec_args exec_args = { + .sshdr = &sshdr, + }; + + spin_lock(&ctlr->ms_lock); + list_splice_init(&ctlr->ms_head, &list); + ctlr->ms_queued = 0; + ctlr->ms_sdev = NULL; + spin_unlock(&ctlr->ms_lock); + + retry: + memset(cdb, 0, sizeof(cdb)); + + data_size = rdac_failover_get(ctlr, &list, cdb); + + RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, " + "%s MODE_SELECT command", + (char *) h->ctlr->array_name, h->ctlr->index, + (retry_cnt == RDAC_RETRY_COUNT) ? "queueing" : "retrying"); + + if (scsi_execute_cmd(sdev, cdb, opf, &h->ctlr->mode_select, data_size, + RDAC_TIMEOUT * HZ, RDAC_RETRIES, &exec_args)) { + err = mode_select_handle_sense(sdev, &sshdr); + if (err == SCSI_DH_RETRY && retry_cnt--) + goto retry; + if (err == SCSI_DH_IMM_RETRY) + goto retry; + } + if (err == SCSI_DH_OK) { + h->state = RDAC_STATE_ACTIVE; + RDAC_LOG(RDAC_LOG_FAILOVER, sdev, "array %s, ctlr %d, " + "MODE_SELECT completed", + (char *) h->ctlr->array_name, h->ctlr->index); + } + + list_for_each_entry_safe(qdata, tmp, &list, entry) { + list_del(&qdata->entry); + if (err == SCSI_DH_OK) + qdata->h->state = RDAC_STATE_ACTIVE; + if (qdata->callback_fn) + qdata->callback_fn(qdata->callback_data, err); + kfree(qdata); + } + return; +} + +static int queue_mode_select(struct scsi_device *sdev, + activate_complete fn, void *data) +{ + struct rdac_queue_data *qdata; + struct rdac_controller *ctlr; + + qdata = kzalloc(sizeof(*qdata), GFP_KERNEL); + if (!qdata) + return SCSI_DH_RETRY; + + qdata->h = sdev->handler_data; + qdata->callback_fn = fn; + qdata->callback_data = data; + + ctlr = qdata->h->ctlr; + spin_lock(&ctlr->ms_lock); + list_add_tail(&qdata->entry, &ctlr->ms_head); + if (!ctlr->ms_queued) { + ctlr->ms_queued = 1; + ctlr->ms_sdev = sdev; + queue_work(kmpath_rdacd, &ctlr->ms_work); + } + spin_unlock(&ctlr->ms_lock); + return SCSI_DH_OK; +} + +static int rdac_activate(struct scsi_device *sdev, + activate_complete fn, void *data) +{ + struct rdac_dh_data *h = sdev->handler_data; + int err = SCSI_DH_OK; + int act = 0; + + err = check_ownership(sdev, h); + if (err != SCSI_DH_OK) + goto done; + + switch (h->mode) { + case RDAC_MODE: + if (h->lun_state == RDAC_LUN_UNOWNED) + act = 1; + break; + case RDAC_MODE_IOSHIP: + if ((h->lun_state == RDAC_LUN_UNOWNED) && + (h->preferred == RDAC_PREFERRED)) + act = 1; + break; + default: + break; + } + + if (act) { + err = queue_mode_select(sdev, fn, data); + if (err == SCSI_DH_OK) + return 0; + } +done: + if (fn) + fn(data, err); + return 0; +} + +static blk_status_t rdac_prep_fn(struct scsi_device *sdev, struct request *req) +{ + struct rdac_dh_data *h = sdev->handler_data; + + if (h->state != RDAC_STATE_ACTIVE) { + req->rq_flags |= RQF_QUIET; + return BLK_STS_IOERR; + } + + return BLK_STS_OK; +} + +static enum scsi_disposition rdac_check_sense(struct scsi_device *sdev, + struct scsi_sense_hdr *sense_hdr) +{ + struct rdac_dh_data *h = sdev->handler_data; + + RDAC_LOG(RDAC_LOG_SENSE, sdev, "array %s, ctlr %d, " + "I/O returned with sense %02x/%02x/%02x", + (char *) h->ctlr->array_name, h->ctlr->index, + sense_hdr->sense_key, sense_hdr->asc, sense_hdr->ascq); + + switch (sense_hdr->sense_key) { + case NOT_READY: + if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x01) + /* LUN Not Ready - Logical Unit Not Ready and is in + * the process of becoming ready + * Just retry. + */ + return ADD_TO_MLQUEUE; + 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; + if (sense_hdr->asc == 0xA1 && sense_hdr->ascq == 0x02) + /* LUN Not Ready - Quiescense in progress + * or has been achieved + * Just retry. + */ + 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; + if (sense_hdr->asc == 0x8b && sense_hdr->ascq == 0x02) + /* + * Quiescence in progress , just retry. + */ + return ADD_TO_MLQUEUE; + break; + } + /* success just means we do not care what scsi-ml does */ + return SCSI_RETURN_NOT_HANDLED; +} + +static int rdac_bus_attach(struct scsi_device *sdev) +{ + struct rdac_dh_data *h; + int err; + char array_name[ARRAY_LABEL_LEN]; + char array_id[UNIQUE_ID_LEN]; + + h = kzalloc(sizeof(*h) , GFP_KERNEL); + if (!h) + return SCSI_DH_NOMEM; + h->lun = UNINITIALIZED_LUN; + h->state = RDAC_STATE_ACTIVE; + + err = get_lun_info(sdev, h, array_name, array_id); + if (err != SCSI_DH_OK) + goto failed; + + err = initialize_controller(sdev, h, array_name, array_id); + if (err != SCSI_DH_OK) + goto failed; + + err = check_ownership(sdev, h); + if (err != SCSI_DH_OK) + goto clean_ctlr; + + err = set_mode_select(sdev, h); + if (err != SCSI_DH_OK) + goto clean_ctlr; + + sdev_printk(KERN_NOTICE, sdev, + "%s: LUN %d (%s) (%s)\n", + RDAC_NAME, h->lun, mode[(int)h->mode], + lun_state[(int)h->lun_state]); + + sdev->handler_data = h; + return SCSI_DH_OK; + +clean_ctlr: + spin_lock(&list_lock); + kref_put(&h->ctlr->kref, release_controller); + spin_unlock(&list_lock); + +failed: + kfree(h); + return err; +} + +static void rdac_bus_detach( struct scsi_device *sdev ) +{ + struct rdac_dh_data *h = sdev->handler_data; + + if (h->ctlr && h->ctlr->ms_queued) + flush_workqueue(kmpath_rdacd); + + spin_lock(&list_lock); + if (h->ctlr) { + list_del_rcu(&h->node); + kref_put(&h->ctlr->kref, release_controller); + } + spin_unlock(&list_lock); + sdev->handler_data = NULL; + synchronize_rcu(); + kfree(h); +} + +static struct scsi_device_handler rdac_dh = { + .name = RDAC_NAME, + .module = THIS_MODULE, + .prep_fn = rdac_prep_fn, + .check_sense = rdac_check_sense, + .attach = rdac_bus_attach, + .detach = rdac_bus_detach, + .activate = rdac_activate, +}; + +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."); + goto done; + } + + /* + * Create workqueue to handle mode selects for rdac + */ + kmpath_rdacd = create_singlethread_workqueue("kmpath_rdacd"); + if (!kmpath_rdacd) { + scsi_unregister_device_handler(&rdac_dh); + printk(KERN_ERR "kmpath_rdacd creation failed.\n"); + + r = -EINVAL; + } +done: + return r; +} + +static void __exit rdac_exit(void) +{ + destroy_workqueue(kmpath_rdacd); + scsi_unregister_device_handler(&rdac_dh); +} + +module_init(rdac_init); +module_exit(rdac_exit); + +MODULE_DESCRIPTION("Multipath LSI/Engenio/NetApp E-Series RDAC driver"); +MODULE_AUTHOR("Mike Christie, Chandra Seetharaman"); +MODULE_VERSION("01.00.0000.0000"); +MODULE_LICENSE("GPL"); |