On 9/1/2015 8:38 PM, lduncan@xxxxxxxx wrote:
From: Lee Duncan <lduncan@xxxxxxxx> Each Scsi_host instance gets a host number starting at 0, but this is implemented with an atomic integer, and rollover doesn't seem to have been considered. Another side-effect of this design is that scsi host numbers used by iscsi are never reused, thereby making rollover more likely. This patch converts Scsi_host instances to use ida to manage their instance numbers. This also means that host instance numbers will be reused, when available. Changes from v1: * Added inline host_put_index() and its use Signed-off-by: Lee Duncan <lduncan@xxxxxxxx> Reviewed-by: Hannes Reinecke <hare@xxxxxxxx> Reviewed-by: Johannes Thumshirn <jthumshirn@xxxxxxx> --- drivers/scsi/hosts.c | 47 +++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 39 insertions(+), 8 deletions(-) diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c index 8bb173e01084..36cb65612821 100644 --- a/drivers/scsi/hosts.c +++ b/drivers/scsi/hosts.c @@ -33,7 +33,7 @@ #include <linux/transport_class.h> #include <linux/platform_device.h> #include <linux/pm_runtime.h> - +#include <linux/idr.h> #include <scsi/scsi_device.h> #include <scsi/scsi_host.h> #include <scsi/scsi_transport.h> @@ -42,7 +42,8 @@ #include "scsi_logging.h" -static atomic_t scsi_host_next_hn = ATOMIC_INIT(0); /* host_no for next new host */ +static DEFINE_SPINLOCK(host_index_lock); +static DEFINE_IDA(host_index_ida); static void scsi_host_cls_release(struct device *dev) @@ -337,6 +338,10 @@ static void scsi_host_dev_release(struct device *dev) kfree(shost->shost_data); + spin_lock(&host_index_lock); + ida_remove(&host_index_ida, shost->host_no); + spin_unlock(&host_index_lock);
Why not host_put_index(index)? -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
