On 09/01/2015 01:23 AM, Sagi Grimberg wrote: > On 8/31/2015 11:28 PM, leeman.duncan@xxxxxxxxx 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. >> >> Signed-off-by: Lee Duncan <lduncan@xxxxxxxx> >> --- >> drivers/scsi/hosts.c | 43 +++++++++++++++++++++++++++++++++++-------- >> 1 file changed, 35 insertions(+), 8 deletions(-) >> >> diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c >> index 8bb173e01084..dade75478541 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 get it in a symmetrical host_put_index() Seems like a reasonable suggestion. Since it's only 3 statements, I'll make it an inline. I will resubmit the patch, adding the two reviewed-by lines from Hannes and Johannes, since the code will essentially be the same. -- Lee Duncan SUSE Labs -- 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
