[SCSI] dm mpath: propagate target errors immediately

DM now has more information about the nature of the underlying storage
failure.  Path failure is avoided if a request failed due to a target
error.  Instead the target error is immediately passed up the stack.

Discard requests that fail due to non-target errors may now be retried.

Errors restricted to the path will be retried or returned if no
paths are available, irregarding the no_path_retry setting.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
This commit is contained in:
Hannes Reinecke 2011-01-18 10:13:12 +01:00 committed by James Bottomley
parent 63583cca74
commit 751b2a7d62

View File

@ -1283,24 +1283,22 @@ static int do_end_io(struct multipath *m, struct request *clone,
if (!error && !clone->errors)
return 0; /* I/O complete */
if (error == -EOPNOTSUPP)
return error;
if (clone->cmd_flags & REQ_DISCARD)
/*
* Pass all discard request failures up.
* FIXME: only fail_path if the discard failed due to a
* transport problem. This requires precise understanding
* of the underlying failure (e.g. the SCSI sense).
*/
if (error == -EOPNOTSUPP || error == -EREMOTEIO)
return error;
if (mpio->pgpath)
fail_path(mpio->pgpath);
spin_lock_irqsave(&m->lock, flags);
if (!m->nr_valid_paths && !m->queue_if_no_path && !__must_push_back(m))
r = -EIO;
if (!m->nr_valid_paths) {
if (!m->queue_if_no_path) {
if (!__must_push_back(m))
r = -EIO;
} else {
if (error == -EBADE)
r = error;
}
}
spin_unlock_irqrestore(&m->lock, flags);
return r;