From a64358db1253b35d508a411e80a3ad23b859ec88 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Tue, 26 Jul 2005 10:27:10 -0400 Subject: [PATCH] [SCSI] SCSI scanning and removal fixes This patch (as545) fixes the list traversals in __scsi_remove_target and scsi_forget_host. In each case the existing code list_for_each_entry_safe in an _unsafe_ manner, because the list was not protected from outside modification while the iteration was running. The new scsi_forget_host routine takes the moderately controversial step of iterating over devices for removal rather than iterating over targets. This makes more sense to me because the current scheme treats targets as second-class citizens, created and removed on demand, rather than as objects corresponding to actual hardware. (Also I couldn't figure out any safe way to iterate over the target list, since it's not so easy to tell when a target has already been removed.) Signed-off-by: Alan Stern Signed-off-by: James Bottomley --- drivers/scsi/scsi_scan.c | 20 +++++++------------- drivers/scsi/scsi_sysfs.c | 9 ++++++--- 2 files changed, 13 insertions(+), 16 deletions(-) diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index b86f170fa8e..fcf9f6cbb14 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -1466,23 +1466,17 @@ EXPORT_SYMBOL(scsi_scan_single_target); void scsi_forget_host(struct Scsi_Host *shost) { - struct scsi_target *starget, *tmp; + struct scsi_device *sdev; unsigned long flags; - /* - * Ok, this look a bit strange. We always look for the first device - * on the list as scsi_remove_device removes them from it - thus we - * also have to release the lock. - * We don't need to get another reference to the device before - * releasing the lock as we already own the reference from - * scsi_register_device that's release in scsi_remove_device. And - * after that we don't look at sdev anymore. - */ + restart: spin_lock_irqsave(shost->host_lock, flags); - list_for_each_entry_safe(starget, tmp, &shost->__targets, siblings) { + list_for_each_entry(sdev, &shost->__devices, siblings) { + if (sdev->sdev_state == SDEV_DEL) + continue; spin_unlock_irqrestore(shost->host_lock, flags); - scsi_remove_target(&starget->dev); - spin_lock_irqsave(shost->host_lock, flags); + __scsi_remove_device(sdev); + goto restart; } spin_unlock_irqrestore(shost->host_lock, flags); } diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c index 83f87c41b18..1e47b7eddef 100644 --- a/drivers/scsi/scsi_sysfs.c +++ b/drivers/scsi/scsi_sysfs.c @@ -719,17 +719,20 @@ void __scsi_remove_target(struct scsi_target *starget) { struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); unsigned long flags; - struct scsi_device *sdev, *tmp; + struct scsi_device *sdev; spin_lock_irqsave(shost->host_lock, flags); starget->reap_ref++; - list_for_each_entry_safe(sdev, tmp, &shost->__devices, siblings) { + restart: + list_for_each_entry(sdev, &shost->__devices, siblings) { if (sdev->channel != starget->channel || - sdev->id != starget->id) + sdev->id != starget->id || + sdev->sdev_state == SDEV_DEL) continue; spin_unlock_irqrestore(shost->host_lock, flags); scsi_remove_device(sdev); spin_lock_irqsave(shost->host_lock, flags); + goto restart; } spin_unlock_irqrestore(shost->host_lock, flags); scsi_target_reap(starget); -- 2.41.1