diff options
author | Mike Snitzer <snitzer@redhat.com> | 2012-06-26 20:32:03 +0200 |
---|---|---|
committer | James Bottomley <JBottomley@Parallels.com> | 2012-07-20 09:58:42 +0200 |
commit | 7e8a74b177f17d100916b6ad415450f7c9508691 (patch) | |
tree | 3a2ed38f030ef3e79d3c332c594dbad89d7642bf /drivers/scsi/device_handler | |
parent | [SCSI] cxgb4i: tcp push bit fix (diff) | |
download | linux-7e8a74b177f17d100916b6ad415450f7c9508691.tar.xz linux-7e8a74b177f17d100916b6ad415450f7c9508691.zip |
[SCSI] scsi_dh: add scsi_dh_attached_handler_name
Introduce scsi_dh_attached_handler_name() to retrieve the name of the
scsi_dh that is attached to the scsi_device associated with the provided
request queue. Returns NULL if a scsi_dh is not attached.
Also, fix scsi_dh_{attach,detach} function header comments to document
@q rather than @sdev.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Tested-by: Babu Moger <babu.moger@netapp.com>
Reviewed-by: Chandra Seetharaman <sekharan@us.ibm.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Diffstat (limited to 'drivers/scsi/device_handler')
-rw-r--r-- | drivers/scsi/device_handler/scsi_dh.c | 38 |
1 files changed, 36 insertions, 2 deletions
diff --git a/drivers/scsi/device_handler/scsi_dh.c b/drivers/scsi/device_handler/scsi_dh.c index 48e46f5b77cc..33e422e75835 100644 --- a/drivers/scsi/device_handler/scsi_dh.c +++ b/drivers/scsi/device_handler/scsi_dh.c @@ -468,7 +468,8 @@ EXPORT_SYMBOL_GPL(scsi_dh_handler_exist); /* * scsi_dh_attach - Attach device handler - * @sdev - sdev the handler should be attached to + * @q - Request queue that is associated with the scsi_device + * the handler should be attached to * @name - name of the handler to attach */ int scsi_dh_attach(struct request_queue *q, const char *name) @@ -498,7 +499,8 @@ EXPORT_SYMBOL_GPL(scsi_dh_attach); /* * scsi_dh_detach - Detach device handler - * @sdev - sdev the handler should be detached from + * @q - Request queue that is associated with the scsi_device + * 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 @@ -527,6 +529,38 @@ void scsi_dh_detach(struct request_queue *q) } EXPORT_SYMBOL_GPL(scsi_dh_detach); +/* + * scsi_dh_attached_handler_name - Get attached device handler's name + * @q - Request queue that is associated with the scsi_device + * that may have a device handler attached + * @gfp - the GFP mask used in the kmalloc() call when allocating memory + * + * Returns name of attached handler, NULL if no handler is attached. + * Caller must take care to free the returned string. + */ +const char *scsi_dh_attached_handler_name(struct request_queue *q, gfp_t gfp) +{ + unsigned long flags; + struct scsi_device *sdev; + const char *handler_name = 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 NULL; + + if (sdev->scsi_dh_data) + handler_name = kstrdup(sdev->scsi_dh_data->scsi_dh->name, gfp); + + put_device(&sdev->sdev_gendev); + return handler_name; +} +EXPORT_SYMBOL_GPL(scsi_dh_attached_handler_name); + static struct notifier_block scsi_dh_nb = { .notifier_call = scsi_dh_notifier }; |