Add a new kernel config option CONFIG_LATE_ROOT_MOUNT that makes the kernel[...]
wait until background scanning of USB mass storage devices is complete before
attempting to mount the root filesystem.
The config option is an alternative to the root_delay= kernel parameter
solution people currently use to boot from USB mass storage devices.
drivers/scsi/scsi_scan.c | 2 ++[...]
drivers/usb/storage/usb.c | 3 +++
include/linux/init.h | 12 ++++++++++++
init/Kconfig | 5 +++++
init/do_mounts.c | 32 ++++++++++++++++++++++++++++++++
5 files changed, 54 insertions(+)
Index: linux-2.6/drivers/usb/storage/usb.c
===================================================================
--- linux-2.6.orig/drivers/usb/storage/usb.c
+++ linux-2.6/drivers/usb/storage/usb.c
@@ -928,6 +928,7 @@ static int usb_stor_scan_thread(void * _
/* Should we unbind if no devices were detected? */
}
+ complete_root_scan();
complete_and_exit(&us->scanning_done, 0);
}
@@ -1007,12 +1008,14 @@ static int storage_probe(struct usb_inte
goto BadDevice;
}
+ begin_root_scan();
/* Start up the thread for delayed SCSI-device scanning */
th = kthread_create(usb_stor_scan_thread, us, "usb-stor-scan");
if (IS_ERR(th)) {
printk(KERN_WARNING USB_STORAGE "Unable to start the device-scanning thread\n");
quiesce_and_remove_host(us);
+ complete_root_scan();
result = PTR_ERR(th);
goto BadDevice;
}
Index: linux-2.6/drivers/scsi/scsi_scan.c
===================================================================
--- linux-2.6.orig/drivers/scsi/scsi_scan.c
+++ linux-2.6/drivers/scsi/scsi_scan.c
@@ -1802,6 +1802,7 @@ static int do_scan_async(void *_data)
struct async_scan_data *data = _data;
do_scsi_scan_host(data->shost);
scsi_finish_async_scan(data);
+ complete_root_scan();
return 0;
}
@@ -1823,6 +1824,7 @@ void scsi_scan_host(struct Scsi_Host *sh
return;
}
+ begin_root_scan();
p = kthread_run(do_scan_async, data, "scsi_scan_%d", shost->host_no);
if (unlikely(IS_ERR(p)))
do_scan_async(data);