From 65f27f38446e1976cc98fd3004b110fedcddd189 Mon Sep 17 00:00:00 2001 From: David Howells Date: Wed, 22 Nov 2006 14:55:48 +0000 Subject: WorkStruct: Pass the work_struct pointer instead of context data Pass the work_struct pointer to the work function rather than context data. The work function can use container_of() to work out the data. For the cases where the container of the work_struct may go away the moment the pending bit is cleared, it is made possible to defer the release of the structure by deferring the clearing of the pending bit. To make this work, an extra flag is introduced into the management side of the work_struct. This governs auto-release of the structure upon execution. Ordinarily, the work queue executor would release the work_struct for further scheduling or deallocation by clearing the pending bit prior to jumping to the work function. This means that, unless the driver makes some guarantee itself that the work_struct won't go away, the work function may not access anything else in the work_struct or its container lest they be deallocated.. This is a problem if the auxiliary data is taken away (as done by the last patch). However, if the pending bit is *not* cleared before jumping to the work function, then the work function *may* access the work_struct and its container with no problems. But then the work function must itself release the work_struct by calling work_release(). In most cases, automatic release is fine, so this is the default. Special initiators exist for the non-auto-release case (ending in _NAR). Signed-Off-By: David Howells --- drivers/scsi/scsi_scan.c | 7 ++++--- drivers/scsi/scsi_sysfs.c | 10 +++++----- 2 files changed, 9 insertions(+), 8 deletions(-) (limited to 'drivers/scsi') diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index 94a274645f6..d3c5e964c96 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -362,9 +362,10 @@ static struct scsi_target *scsi_alloc_target(struct device *parent, goto retry; } -static void scsi_target_reap_usercontext(void *data) +static void scsi_target_reap_usercontext(struct work_struct *work) { - struct scsi_target *starget = data; + struct scsi_target *starget = + container_of(work, struct scsi_target, ew.work); struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); unsigned long flags; @@ -400,7 +401,7 @@ void scsi_target_reap(struct scsi_target *starget) starget->state = STARGET_DEL; spin_unlock_irqrestore(shost->host_lock, flags); execute_in_process_context(scsi_target_reap_usercontext, - starget, &starget->ew); + &starget->ew); return; } diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c index e1a91665d1c..259c90cfa36 100644 --- a/drivers/scsi/scsi_sysfs.c +++ b/drivers/scsi/scsi_sysfs.c @@ -218,16 +218,16 @@ static void scsi_device_cls_release(struct class_device *class_dev) put_device(&sdev->sdev_gendev); } -static void scsi_device_dev_release_usercontext(void *data) +static void scsi_device_dev_release_usercontext(struct work_struct *work) { - struct device *dev = data; struct scsi_device *sdev; struct device *parent; struct scsi_target *starget; unsigned long flags; - parent = dev->parent; - sdev = to_scsi_device(dev); + sdev = container_of(work, struct scsi_device, ew.work); + + parent = sdev->sdev_gendev.parent; starget = to_scsi_target(parent); spin_lock_irqsave(sdev->host->host_lock, flags); @@ -258,7 +258,7 @@ static void scsi_device_dev_release_usercontext(void *data) static void scsi_device_dev_release(struct device *dev) { struct scsi_device *sdp = to_scsi_device(dev); - execute_in_process_context(scsi_device_dev_release_usercontext, dev, + execute_in_process_context(scsi_device_dev_release_usercontext, &sdp->ew); } -- cgit v1.2.3