Commit d0259bf0 authored Mar 06, 2010 by Kiyoshi Ueda Committed by Alasdair G Kergon Mar 06, 2010

dm mpath: hold io until all pg_inits completed



m->queue_io is set to block processing I/Os, and it needs to be kept
while pg-init, which issues multiple path activations, is in progress.
But m->queue is cleared when a path activation completes without error
in pg_init_done(), even while other path activations are in progress.
That may cause undesired -EIO on paths which are not complete activation.

This patch fixes that by not clearing m->queue_io until all path
activations complete.

(Before the hardware handlers were moved into the SCSI layer, pg_init
only used one path.)

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

parent fce323dd

drivers/md/dm-mpath.c

+11 −6

Original line number	Diff line number	Diff line
		@@ -1181,14 +1181,19 @@ static void pg_init_done(void *data, int errors)
		m->current_pgpath = NULL;
		m->current_pg = NULL;
		}
		} else if (!m->pg_init_required) {
		m->queue_io = 0;
		} else if (!m->pg_init_required)
		pg->bypassed = 0;
		}

		m->pg_init_in_progress--;
		if (!m->pg_init_in_progress)
		if (--m->pg_init_in_progress)
		/* Activations of other paths are still on going */
		goto out;

		if (!m->pg_init_required)
		m->queue_io = 0;

		queue_work(kmultipathd, &m->process_queued_ios);

		out:
		spin_unlock_irqrestore(&m->lock, flags);
		}

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