diff options
Diffstat (limited to 'drivers/md/dm-hw-handler.c')
-rw-r--r-- | drivers/md/dm-hw-handler.c | 213 |
1 files changed, 0 insertions, 213 deletions
diff --git a/drivers/md/dm-hw-handler.c b/drivers/md/dm-hw-handler.c deleted file mode 100644 index 2ee84d8aa0bf..000000000000 --- a/drivers/md/dm-hw-handler.c +++ /dev/null @@ -1,213 +0,0 @@ -/* - * Copyright (C) 2004 Red Hat, Inc. All rights reserved. - * - * This file is released under the GPL. - * - * Multipath hardware handler registration. - */ - -#include "dm.h" -#include "dm-hw-handler.h" - -#include <linux/slab.h> - -struct hwh_internal { - struct hw_handler_type hwht; - - struct list_head list; - long use; -}; - -#define hwht_to_hwhi(__hwht) container_of((__hwht), struct hwh_internal, hwht) - -static LIST_HEAD(_hw_handlers); -static DECLARE_RWSEM(_hwh_lock); - -static struct hwh_internal *__find_hw_handler_type(const char *name) -{ - struct hwh_internal *hwhi; - - list_for_each_entry(hwhi, &_hw_handlers, list) { - if (!strcmp(name, hwhi->hwht.name)) - return hwhi; - } - - return NULL; -} - -static struct hwh_internal *get_hw_handler(const char *name) -{ - struct hwh_internal *hwhi; - - down_read(&_hwh_lock); - hwhi = __find_hw_handler_type(name); - if (hwhi) { - if ((hwhi->use == 0) && !try_module_get(hwhi->hwht.module)) - hwhi = NULL; - else - hwhi->use++; - } - up_read(&_hwh_lock); - - return hwhi; -} - -struct hw_handler_type *dm_get_hw_handler(const char *name) -{ - struct hwh_internal *hwhi; - - if (!name) - return NULL; - - hwhi = get_hw_handler(name); - if (!hwhi) { - request_module("dm-%s", name); - hwhi = get_hw_handler(name); - } - - return hwhi ? &hwhi->hwht : NULL; -} - -void dm_put_hw_handler(struct hw_handler_type *hwht) -{ - struct hwh_internal *hwhi; - - if (!hwht) - return; - - down_read(&_hwh_lock); - hwhi = __find_hw_handler_type(hwht->name); - if (!hwhi) - goto out; - - if (--hwhi->use == 0) - module_put(hwhi->hwht.module); - - BUG_ON(hwhi->use < 0); - - out: - up_read(&_hwh_lock); -} - -static struct hwh_internal *_alloc_hw_handler(struct hw_handler_type *hwht) -{ - struct hwh_internal *hwhi = kzalloc(sizeof(*hwhi), GFP_KERNEL); - - if (hwhi) - hwhi->hwht = *hwht; - - return hwhi; -} - -int dm_register_hw_handler(struct hw_handler_type *hwht) -{ - int r = 0; - struct hwh_internal *hwhi = _alloc_hw_handler(hwht); - - if (!hwhi) - return -ENOMEM; - - down_write(&_hwh_lock); - - if (__find_hw_handler_type(hwht->name)) { - kfree(hwhi); - r = -EEXIST; - } else - list_add(&hwhi->list, &_hw_handlers); - - up_write(&_hwh_lock); - - return r; -} - -int dm_unregister_hw_handler(struct hw_handler_type *hwht) -{ - struct hwh_internal *hwhi; - - down_write(&_hwh_lock); - - hwhi = __find_hw_handler_type(hwht->name); - if (!hwhi) { - up_write(&_hwh_lock); - return -EINVAL; - } - - if (hwhi->use) { - up_write(&_hwh_lock); - return -ETXTBSY; - } - - list_del(&hwhi->list); - - up_write(&_hwh_lock); - - kfree(hwhi); - - return 0; -} - -unsigned dm_scsi_err_handler(struct hw_handler *hwh, struct bio *bio) -{ -#if 0 - int sense_key, asc, ascq; - - if (bio->bi_error & BIO_SENSE) { - /* FIXME: This is just an initial guess. */ - /* key / asc / ascq */ - sense_key = (bio->bi_error >> 16) & 0xff; - asc = (bio->bi_error >> 8) & 0xff; - ascq = bio->bi_error & 0xff; - - switch (sense_key) { - /* This block as a whole comes from the device. - * So no point retrying on another path. */ - case 0x03: /* Medium error */ - case 0x05: /* Illegal request */ - case 0x07: /* Data protect */ - case 0x08: /* Blank check */ - case 0x0a: /* copy aborted */ - case 0x0c: /* obsolete - no clue ;-) */ - case 0x0d: /* volume overflow */ - case 0x0e: /* data miscompare */ - case 0x0f: /* reserved - no idea either. */ - return MP_ERROR_IO; - - /* For these errors it's unclear whether they - * come from the device or the controller. - * So just lets try a different path, and if - * it eventually succeeds, user-space will clear - * the paths again... */ - case 0x02: /* Not ready */ - case 0x04: /* Hardware error */ - case 0x09: /* vendor specific */ - case 0x0b: /* Aborted command */ - return MP_FAIL_PATH; - - case 0x06: /* Unit attention - might want to decode */ - if (asc == 0x04 && ascq == 0x01) - /* "Unit in the process of - * becoming ready" */ - return 0; - return MP_FAIL_PATH; - - /* FIXME: For Unit Not Ready we may want - * to have a generic pg activation - * feature (START_UNIT). */ - - /* Should these two ever end up in the - * error path? I don't think so. */ - case 0x00: /* No sense */ - case 0x01: /* Recovered error */ - return 0; - } - } -#endif - - /* We got no idea how to decode the other kinds of errors -> - * assume generic error condition. */ - return MP_FAIL_PATH; -} - -EXPORT_SYMBOL_GPL(dm_register_hw_handler); -EXPORT_SYMBOL_GPL(dm_unregister_hw_handler); -EXPORT_SYMBOL_GPL(dm_scsi_err_handler); |