diff options
Diffstat (limited to 'drivers/md/dm-emc.c')
| -rw-r--r-- | drivers/md/dm-emc.c | 345 |
1 files changed, 0 insertions, 345 deletions
diff --git a/drivers/md/dm-emc.c b/drivers/md/dm-emc.c deleted file mode 100644 index 3ea5ad4b7805..000000000000 --- a/drivers/md/dm-emc.c +++ /dev/null @@ -1,345 +0,0 @@ -/* - * Copyright (C) 2004 SUSE LINUX Products GmbH. All rights reserved. - * Copyright (C) 2004 Red Hat, Inc. All rights reserved. - * - * This file is released under the GPL. - * - * Multipath support for EMC CLARiiON AX/CX-series hardware. - */ - -#include "dm.h" -#include "dm-hw-handler.h" -#include <scsi/scsi.h> -#include <scsi/scsi_cmnd.h> - -#define DM_MSG_PREFIX "multipath emc" - -struct emc_handler { - spinlock_t lock; - - /* Whether we should send the short trespass command (FC-series) - * or the long version (default for AX/CX CLARiiON arrays). */ - unsigned short_trespass; - /* Whether or not to honor SCSI reservations when initiating a - * switch-over. Default: Don't. */ - unsigned hr; - - unsigned char sense[SCSI_SENSE_BUFFERSIZE]; -}; - -#define TRESPASS_PAGE 0x22 -#define EMC_FAILOVER_TIMEOUT (60 * HZ) - -/* Code borrowed from dm-lsi-rdac by Mike Christie */ - -static inline void free_bio(struct bio *bio) -{ - __free_page(bio->bi_io_vec[0].bv_page); - bio_put(bio); -} - -static void emc_endio(struct bio *bio, int error) -{ - struct dm_path *path = bio->bi_private; - - /* We also need to look at the sense keys here whether or not to - * switch to the next PG etc. - * - * For now simple logic: either it works or it doesn't. - */ - if (error) - dm_pg_init_complete(path, MP_FAIL_PATH); - else - dm_pg_init_complete(path, 0); - - /* request is freed in block layer */ - free_bio(bio); -} - -static struct bio *get_failover_bio(struct dm_path *path, unsigned data_size) -{ - struct bio *bio; - struct page *page; - - bio = bio_alloc(GFP_ATOMIC, 1); - if (!bio) { - DMERR("get_failover_bio: bio_alloc() failed."); - return NULL; - } - - bio->bi_rw |= (1 << BIO_RW); - bio->bi_bdev = path->dev->bdev; - bio->bi_sector = 0; - bio->bi_private = path; - bio->bi_end_io = emc_endio; - - page = alloc_page(GFP_ATOMIC); - if (!page) { - DMERR("get_failover_bio: alloc_page() failed."); - bio_put(bio); - return NULL; - } - - if (bio_add_page(bio, page, data_size, 0) != data_size) { - DMERR("get_failover_bio: bio_add_page() failed."); - __free_page(page); - bio_put(bio); - return NULL; - } - - return bio; -} - -static struct request *get_failover_req(struct emc_handler *h, - struct bio *bio, struct dm_path *path) -{ - struct request *rq; - struct block_device *bdev = bio->bi_bdev; - struct request_queue *q = bdev_get_queue(bdev); - - /* FIXME: Figure out why it fails with GFP_ATOMIC. */ - rq = blk_get_request(q, WRITE, __GFP_WAIT); - if (!rq) { - DMERR("get_failover_req: blk_get_request failed"); - return NULL; - } - - blk_rq_append_bio(q, rq, bio); - - rq->sense = h->sense; - memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE); - rq->sense_len = 0; - - rq->timeout = EMC_FAILOVER_TIMEOUT; - rq->cmd_type = REQ_TYPE_BLOCK_PC; - rq->cmd_flags |= REQ_FAILFAST | REQ_NOMERGE; - - return rq; -} - -static struct request *emc_trespass_get(struct emc_handler *h, - struct dm_path *path) -{ - struct bio *bio; - struct request *rq; - unsigned char *page22; - unsigned char long_trespass_pg[] = { - 0, 0, 0, 0, - TRESPASS_PAGE, /* Page code */ - 0x09, /* Page length - 2 */ - h->hr ? 0x01 : 0x81, /* Trespass code + Honor reservation bit */ - 0xff, 0xff, /* Trespass target */ - 0, 0, 0, 0, 0, 0 /* Reserved bytes / unknown */ - }; - unsigned char short_trespass_pg[] = { - 0, 0, 0, 0, - TRESPASS_PAGE, /* Page code */ - 0x02, /* Page length - 2 */ - h->hr ? 0x01 : 0x81, /* Trespass code + Honor reservation bit */ - 0xff, /* Trespass target */ - }; - unsigned data_size = h->short_trespass ? sizeof(short_trespass_pg) : - sizeof(long_trespass_pg); - - /* get bio backing */ - if (data_size > PAGE_SIZE) - /* this should never happen */ - return NULL; - - bio = get_failover_bio(path, data_size); - if (!bio) { - DMERR("emc_trespass_get: no bio"); - return NULL; - } - - page22 = (unsigned char *)bio_data(bio); - memset(page22, 0, data_size); - - memcpy(page22, h->short_trespass ? - short_trespass_pg : long_trespass_pg, data_size); - - /* get request for block layer packet command */ - rq = get_failover_req(h, bio, path); - if (!rq) { - DMERR("emc_trespass_get: no rq"); - free_bio(bio); - return NULL; - } - - /* Prepare the command. */ - rq->cmd[0] = MODE_SELECT; - rq->cmd[1] = 0x10; - rq->cmd[4] = data_size; - rq->cmd_len = COMMAND_SIZE(rq->cmd[0]); - - return rq; -} - -static void emc_pg_init(struct hw_handler *hwh, unsigned bypassed, - struct dm_path *path) -{ - struct request *rq; - struct request_queue *q = bdev_get_queue(path->dev->bdev); - - /* - * We can either blindly init the pg (then look at the sense), - * or we can send some commands to get the state here (then - * possibly send the fo cmnd), or we can also have the - * initial state passed into us and then get an update here. - */ - if (!q) { - DMINFO("emc_pg_init: no queue"); - goto fail_path; - } - - /* FIXME: The request should be pre-allocated. */ - rq = emc_trespass_get(hwh->context, path); - if (!rq) { - DMERR("emc_pg_init: no rq"); - goto fail_path; - } - - DMINFO("emc_pg_init: sending switch-over command"); - elv_add_request(q, rq, ELEVATOR_INSERT_FRONT, 1); - return; - -fail_path: - dm_pg_init_complete(path, MP_FAIL_PATH); -} - -static struct emc_handler *alloc_emc_handler(void) -{ - struct emc_handler *h = kzalloc(sizeof(*h), GFP_KERNEL); - - if (h) - spin_lock_init(&h->lock); - - return h; -} - -static int emc_create(struct hw_handler *hwh, unsigned argc, char **argv) -{ - struct emc_handler *h; - unsigned hr, short_trespass; - - if (argc == 0) { - /* No arguments: use defaults */ - hr = 0; - short_trespass = 0; - } else if (argc != 2) { - DMWARN("incorrect number of arguments"); - return -EINVAL; - } else { - if ((sscanf(argv[0], "%u", &short_trespass) != 1) - || (short_trespass > 1)) { - DMWARN("invalid trespass mode selected"); - return -EINVAL; - } - - if ((sscanf(argv[1], "%u", &hr) != 1) - || (hr > 1)) { - DMWARN("invalid honor reservation flag selected"); - return -EINVAL; - } - } - - h = alloc_emc_handler(); - if (!h) - return -ENOMEM; - - hwh->context = h; - - if ((h->short_trespass = short_trespass)) - DMWARN("short trespass command will be send"); - else - DMWARN("long trespass command will be send"); - - if ((h->hr = hr)) - DMWARN("honor reservation bit will be set"); - else - DMWARN("honor reservation bit will not be set (default)"); - - return 0; -} - -static void emc_destroy(struct hw_handler *hwh) -{ - struct emc_handler *h = (struct emc_handler *) hwh->context; - - kfree(h); - hwh->context = NULL; -} - -static unsigned emc_error(struct hw_handler *hwh, struct bio *bio) -{ - /* FIXME: Patch from axboe still missing */ -#if 0 - int sense; - - if (bio->bi_error & BIO_SENSE) { - sense = bio->bi_error & 0xffffff; /* sense key / asc / ascq */ - - if (sense == 0x020403) { - /* 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. */ - return MP_BYPASS_PG | MP_RETRY_IO; - } else if (sense == 0x052501) { - /* 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.) */ - return 0; - } else if (sense == 0x062900) { - /* Unit Attention Code. This is the first IO - * to the new path, so just retry. */ - return MP_RETRY_IO; - } - } -#endif - - /* Try default handler */ - return dm_scsi_err_handler(hwh, bio); -} - -static struct hw_handler_type emc_hwh = { - .name = "emc", - .module = THIS_MODULE, - .create = emc_create, - .destroy = emc_destroy, - .pg_init = emc_pg_init, - .error = emc_error, -}; - -static int __init dm_emc_init(void) -{ - int r = dm_register_hw_handler(&emc_hwh); - - if (r < 0) - DMERR("register failed %d", r); - - DMINFO("version 0.0.3 loaded"); - - return r; -} - -static void __exit dm_emc_exit(void) -{ - int r = dm_unregister_hw_handler(&emc_hwh); - - if (r < 0) - DMERR("unregister failed %d", r); -} - -module_init(dm_emc_init); -module_exit(dm_emc_exit); - -MODULE_DESCRIPTION(DM_NAME " EMC CX/AX/FC-family multipath"); -MODULE_AUTHOR("Lars Marowsky-Bree <lmb@suse.de>"); -MODULE_LICENSE("GPL"); |