diff options
Diffstat (limited to 'drivers/scsi/device_handler/scsi_dh_emc.c')
-rw-r--r-- | drivers/scsi/device_handler/scsi_dh_emc.c | 504 |
1 files changed, 504 insertions, 0 deletions
diff --git a/drivers/scsi/device_handler/scsi_dh_emc.c b/drivers/scsi/device_handler/scsi_dh_emc.c new file mode 100644 index 00000000000..f2467e936e5 --- /dev/null +++ b/drivers/scsi/device_handler/scsi_dh_emc.c @@ -0,0 +1,504 @@ +/* + * 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; +} + +static const struct { + char *vendor; + char *model; +} clariion_dev_list[] = { + {"DGC", "RAID"}, + {"DGC", "DISK"}, + {NULL, NULL}, +}; + +static int clariion_bus_notify(struct notifier_block *, unsigned long, void *); + +static struct scsi_device_handler clariion_dh = { + .name = CLARIION_NAME, + .module = THIS_MODULE, + .nb.notifier_call = clariion_bus_notify, + .check_sense = clariion_check_sense, + .activate = clariion_activate, +}; + +/* + * TODO: need some interface so we can set trespass values + */ +static int clariion_bus_notify(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct device *dev = data; + struct scsi_device *sdev; + struct scsi_dh_data *scsi_dh_data; + struct clariion_dh_data *h; + int i, found = 0; + unsigned long flags; + + if (!scsi_is_sdev_device(dev)) + return 0; + + sdev = to_scsi_device(dev); + + if (action == BUS_NOTIFY_ADD_DEVICE) { + for (i = 0; clariion_dev_list[i].vendor; i++) { + if (!strncmp(sdev->vendor, clariion_dev_list[i].vendor, + strlen(clariion_dev_list[i].vendor)) && + !strncmp(sdev->model, clariion_dev_list[i].model, + strlen(clariion_dev_list[i].model))) { + found = 1; + break; + } + } + if (!found) + goto out; + + 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); + goto out; + } + + 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); + + } else if (action == BUS_NOTIFY_DEL_DEVICE) { + if (sdev->scsi_dh_data == NULL || + sdev->scsi_dh_data->scsi_dh != &clariion_dh) + goto out; + + 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, "Dettached %s.\n", + CLARIION_NAME); + + kfree(scsi_dh_data); + module_put(THIS_MODULE); + } + +out: + return 0; +} + +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"); |