From 3e082a910d217b2e7b186077ebf5a1126a68c62f Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Thu, 28 Sep 2006 15:19:20 -0600 Subject: [SCSI] Add ability to scan scsi busses asynchronously Since it often takes around 20-30 seconds to scan a scsi bus, it's highly advantageous to do this in parallel with other things. The bulk of this patch is ensuring that devices don't change numbering, and that all devices are discovered prior to trying to start init. For those who build SCSI as modules, there's a new scsi_wait_scan module that will ensure all bus scans are finished. This patch only handles drivers which call scsi_scan_host. Fibre Channel, SAS, SATA, USB and Firewire all need additional work. Signed-off-by: Matthew Wilcox Signed-off-by: James Bottomley --- include/scsi/scsi_device.h | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-) (limited to 'include/scsi/scsi_device.h') diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index b401c82036b..ebf31b16dc4 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -223,13 +223,13 @@ extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *, struct scsi_device *); /** - * shost_for_each_device - iterate over all devices of a host - * @sdev: iterator - * @host: host whiches devices we want to iterate over + * shost_for_each_device - iterate over all devices of a host + * @sdev: the &struct scsi_device to use as a cursor + * @shost: the &struct scsi_host to iterate over * - * This traverses over each devices of @shost. The devices have - * a reference that must be released by scsi_host_put when breaking - * out of the loop. + * Iterator that returns each device attached to @shost. This loop + * takes a reference on each device and releases it at the end. If + * you break out of the loop, you must call scsi_device_put(sdev). */ #define shost_for_each_device(sdev, shost) \ for ((sdev) = __scsi_iterate_devices((shost), NULL); \ @@ -237,17 +237,17 @@ extern struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *, (sdev) = __scsi_iterate_devices((shost), (sdev))) /** - * __shost_for_each_device - iterate over all devices of a host (UNLOCKED) - * @sdev: iterator - * @host: host whiches devices we want to iterate over + * __shost_for_each_device - iterate over all devices of a host (UNLOCKED) + * @sdev: the &struct scsi_device to use as a cursor + * @shost: the &struct scsi_host to iterate over * - * This traverses over each devices of @shost. It does _not_ take a - * reference on the scsi_device, thus it the whole loop must be protected - * by shost->host_lock. + * Iterator that returns each device attached to @shost. It does _not_ + * take a reference on the scsi_device, so the whole loop must be + * protected by shost->host_lock. * - * Note: The only reason why drivers would want to use this is because - * they're need to access the device list in irq context. Otherwise you - * really want to use shost_for_each_device instead. + * Note: The only reason to use this is because you need to access the + * device list in interrupt context. Otherwise you really want to use + * shost_for_each_device instead. */ #define __shost_for_each_device(sdev, shost) \ list_for_each_entry((sdev), &((shost)->__devices), siblings) -- cgit v1.2.3-18-g5258