diff options
| -rw-r--r-- | drivers/md/dm-mpath.c | 13 | ||||
| -rw-r--r-- | drivers/scsi/device_handler/scsi_dh.c | 64 | ||||
| -rw-r--r-- | include/scsi/scsi_dh.h | 10 |
3 files changed, 87 insertions, 0 deletions
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index fea966d66f98..71dd65aa31b6 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -147,9 +147,12 @@ static struct priority_group *alloc_priority_group(void) static void free_pgpaths(struct list_head *pgpaths, struct dm_target *ti) { struct pgpath *pgpath, *tmp; + struct multipath *m = ti->private; list_for_each_entry_safe(pgpath, tmp, pgpaths, list) { list_del(&pgpath->list); + if (m->hw_handler_name) + scsi_dh_detach(bdev_get_queue(pgpath->path.dev->bdev)); dm_put_device(ti, pgpath->path.dev); free_pgpath(pgpath); } @@ -548,6 +551,7 @@ static struct pgpath *parse_path(struct arg_set *as, struct path_selector *ps, { int r; struct pgpath *p; + struct multipath *m = ti->private; /* we need at least a path arg */ if (as->argc < 1) { @@ -566,6 +570,15 @@ static struct pgpath *parse_path(struct arg_set *as, struct path_selector *ps, goto bad; } + if (m->hw_handler_name) { + r = scsi_dh_attach(bdev_get_queue(p->path.dev->bdev), + m->hw_handler_name); + if (r < 0) { + dm_put_device(ti, p->path.dev); + goto bad; + } + } + r = ps->type->add_path(ps, &p->path, as->argc, as->argv, &ti->error); if (r) { dm_put_device(ti, p->path.dev); diff --git a/drivers/scsi/device_handler/scsi_dh.c b/drivers/scsi/device_handler/scsi_dh.c index e90df9dd3e65..a9159681ff27 100644 --- a/drivers/scsi/device_handler/scsi_dh.c +++ b/drivers/scsi/device_handler/scsi_dh.c @@ -369,6 +369,70 @@ int scsi_dh_handler_exist(const char *name) } EXPORT_SYMBOL_GPL(scsi_dh_handler_exist); +/* + * scsi_dh_handler_attach - Attach device handler + * @sdev - sdev the handler should be attached to + * @name - name of the handler to attach + */ +int scsi_dh_attach(struct request_queue *q, const char *name) +{ + unsigned long flags; + struct scsi_device *sdev; + struct scsi_device_handler *scsi_dh; + int err = 0; + + scsi_dh = get_device_handler(name); + if (!scsi_dh) + return -EINVAL; + + spin_lock_irqsave(q->queue_lock, flags); + sdev = q->queuedata; + if (!sdev || !get_device(&sdev->sdev_gendev)) + err = -ENODEV; + spin_unlock_irqrestore(q->queue_lock, flags); + + if (!err) { + err = scsi_dh_handler_attach(sdev, scsi_dh); + + put_device(&sdev->sdev_gendev); + } + return err; +} +EXPORT_SYMBOL_GPL(scsi_dh_attach); + +/* + * scsi_dh_handler_detach - Detach device handler + * @sdev - sdev the handler should be detached from + * + * This function will detach the device handler only + * if the sdev is not part of the internal list, ie + * if it has been attached manually. + */ +void scsi_dh_detach(struct request_queue *q) +{ + unsigned long flags; + struct scsi_device *sdev; + struct scsi_device_handler *scsi_dh = NULL; + + spin_lock_irqsave(q->queue_lock, flags); + sdev = q->queuedata; + if (!sdev || !get_device(&sdev->sdev_gendev)) + sdev = NULL; + spin_unlock_irqrestore(q->queue_lock, flags); + + if (!sdev) + return; + + if (sdev->scsi_dh_data) { + /* if sdev is not on internal list, detach */ + scsi_dh = sdev->scsi_dh_data->scsi_dh; + if (!device_handler_match(scsi_dh, sdev)) + scsi_dh_handler_detach(sdev, scsi_dh); + } + put_device(&sdev->sdev_gendev); +} +EXPORT_SYMBOL_GPL(scsi_dh_detach); + static struct notifier_block scsi_dh_nb = { .notifier_call = scsi_dh_notifier }; diff --git a/include/scsi/scsi_dh.h b/include/scsi/scsi_dh.h index e15e2aade69c..33efce20c26c 100644 --- a/include/scsi/scsi_dh.h +++ b/include/scsi/scsi_dh.h @@ -58,6 +58,8 @@ enum { #if defined(CONFIG_SCSI_DH) || defined(CONFIG_SCSI_DH_MODULE) extern int scsi_dh_activate(struct request_queue *); extern int scsi_dh_handler_exist(const char *); +extern int scsi_dh_attach(struct request_queue *, const char *); +extern void scsi_dh_detach(struct request_queue *); #else static inline int scsi_dh_activate(struct request_queue *req) { @@ -67,4 +69,12 @@ static inline int scsi_dh_handler_exist(const char *name) { return 0; } +static inline int scsi_dh_attach(struct request_queue *req, const char *name) +{ + return SCSI_DH_NOSYS; +} +static inline void scsi_dh_detach(struct request_queue *q) +{ + return; +} #endif |