aoe: don't call set_capacity from irq context (8a6f7bbf) · Commits · 戴 / test

Updating the block device size from irq context can lead to torn writes of the 64-bit value, and prevents us from using normal process context locking primitives to serialize access to the 64-bit nr_sectors value. Defer the set_capacity to the already existing workqueue handler, where it can be merged with the update of the block device size by using set_capacity_and_notify. As an extra bonus this also adds proper uevent notifications for the resize. Signed-off-by:

Christoph Hellwig <hch@lst.de> Signed-off-by:

Jens Axboe <axboe@kernel.dk>

drivers/block/aoe/aoecmd.c

+4 −11

Original line number	Diff line number	Diff line
		@@ -890,19 +890,13 @@ void
		aoecmd_sleepwork(struct work_struct *work)
		{
		struct aoedev *d = container_of(work, struct aoedev, work);
		struct block_device *bd;
		u64 ssize;

		if (d->flags & DEVFL_GDALLOC)
		aoeblk_gdalloc(d);

		if (d->flags & DEVFL_NEWSIZE) {
		ssize = get_capacity(d->gd);
		bd = bdget_disk(d->gd, 0);
		if (bd) {
		bd_set_nr_sectors(bd, ssize);
		bdput(bd);
		}
		set_capacity_and_notify(d->gd, d->ssize);

		spin_lock_irq(&d->lock);
		d->flags \|= DEVFL_UP;
		d->flags &= ~DEVFL_NEWSIZE;
		@@ -971,10 +965,9 @@ ataid_complete(struct aoedev d, struct aoetgt t, unsigned char *id)
		d->geo.start = 0;
		if (d->flags & (DEVFL_GDALLOC\|DEVFL_NEWSIZE))
		return;
		if (d->gd != NULL) {
		set_capacity(d->gd, ssize);
		if (d->gd != NULL)
		d->flags \|= DEVFL_NEWSIZE;
		} else
		else
		d->flags \|= DEVFL_GDALLOC;
		schedule_work(&d->work);
		}

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