Commit Graph

90 Commits

Author SHA1 Message Date
Mike Snitzer 498f0103ea dm table: share target argument parsing functions
Move multipath target argument parsing code into dm-table so other
targets can share it.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-08-02 12:32:04 +01:00
Mike Snitzer 286f367dad dm mpath: fix potential NULL pointer in feature arg processing
Avoid dereferencing a NULL pointer if the number of feature arguments
supplied is fewer than indicated.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: stable@kernel.org
2011-08-02 12:32:00 +01:00
Arun Sharma 60063497a9 atomic: use <linux/atomic.h>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:47 -07:00
Martin K. Petersen 6f13f6fba7 dm mpath: do not fail paths after integrity errors
Integrity errors need to be passed to the owner of the integrity
metadata for processing. Consequently EILSEQ should be passed up the
stack.

Cc: stable@kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-05-29 13:02:55 +01:00
Mike Snitzer a490a07a67 dm mpath: allow table load with no priority groups
This patch adjusts the multipath target to allow a table with both 0
priority groups and 0 for the initial priority group number.

If any mpath device is held open when all paths in the last priority
group have failed, userspace multipathd will attempt to reload the
associated DM table to reflect the fact that the device no longer has
any priority groups.  But the reload attempt always failed because the
multipath target did not allow 0 priority groups.

All multipath target messages related to priority group (enable_group,
disable_group, switch_group) will handle a priority group of 0 (will
cause error).

When reloading a multipath table with 0 priority groups, userspace
multipathd must be updated to specify an initial priority group number
of 0 (rather than 1).

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: Babu Moger <babu.moger@lsi.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-03-24 13:54:33 +00:00
Mike Snitzer 19040c0bc8 dm mpath: fail message ioctl if specified path is not valid
Fail the reinstate_path and fail_path message ioctl if the specified
path is not valid.

The message ioctl would succeed for the 'reinistate_path' and
'fail_path' messages even if action was not taken because the
specified device was not a valid path of the multipath device.

Before, when /dev/vdb is not a path of mpathb:
$ dmsetup message mpathb 0 reinstate_path /dev/vdb
$ echo $?
0

After:
$ dmsetup message mpathb 0 reinstate_path /dev/vdb
device-mapper: message ioctl failed: Invalid argument
Command failed
$ echo $?
1

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-03-24 13:54:31 +00:00
Hannes Reinecke 751b2a7d62 [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>
2011-02-12 10:33:29 -06:00
Chandra Seetharaman 4e2d19e46b dm mpath: delay activate_path retry on SCSI_DH_RETRY
This patch adds a user-configurable 'pg_init_delay_msecs' feature.  Use
this feature to specify the number of milliseconds to delay before
retrying scsi_dh_activate, when SCSI_DH_RETRY is returned.

SCSI Device Handlers return SCSI_DH_IMM_RETRY if we could retry
activation immediately and SCSI_DH_RETRY in cases where it is better to
retry after some delay.

Currently we immediately retry scsi_dh_activate irrespective of
SCSI_DH_IMM_RETRY and SCSI_DH_RETRY.

The 'pg_init_delay_msecs' feature may be provided during table create or
load, e.g.:
    dmsetup create --table "0 20971520 multipath 3 queue_if_no_path \
	pg_init_delay_msecs 2500 ..." mpatha

The default for 'pg_init_delay_msecs' is 2000 milliseconds.
Maximum configurable delay is 60000 milliseconds.  Specifying a
'pg_init_delay_msecs' of 0 will cause immediate retry.

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Acked-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13 20:00:01 +00:00
Tejun Heo 4d4d66ab53 dm: convert workqueues to alloc_ordered
Convert all create[_singlethread]_work() users to the new
alloc[_ordered]_workqueue().  This conversion is mechanical and
doesn't introduce any behavior change.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13 19:59:57 +00:00
Tejun Heo d5ffa387e2 dm: dont use flush_scheduled_work
flush_scheduled_work() is being deprecated.  Flush the used work
directly instead.  In all dm targets, the only work which uses
system_wq is ->trigger_event.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13 19:59:56 +00:00
Mike Snitzer 09c9d4c9b6 dm mpath: disable blk_abort_queue
Revert commit 224cb3e981
  dm: Call blk_abort_queue on failed paths

Multipath began to use blk_abort_queue() to allow for
lower latency path deactivation.  This was found to
cause list corruption:

   the cmd gets blk_abort_queued/timedout run on it and the scsi eh
   somehow is able to complete and run scsi_queue_insert while
   scsi_request_fn is still trying to process the request.

   https://www.redhat.com/archives/dm-devel/2010-November/msg00085.html

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: Mike Anderson <andmike@linux.vnet.ibm.com>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: stable@kernel.org
2011-01-13 19:59:46 +00:00
Mike Snitzer 959eb4e559 dm mpath: support discard
Enable discard support in the DM multipath target.

This discard support depends on a few discard-specific fixes to the
block layer's request stacking driver methods.

Discard requests are optional so don't allow a failed discard to trigger
path failures.  If there is a real problem with a given path the
barriers associated with the discard (either before or after the
discard) will cause path failure.  That said, unconditionally passing
discard failures up the stack is not ideal.  This must be fixed once DM
has more information about the nature of the underlying storage failure.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
2010-08-12 04:14:32 +01:00
Alasdair G Kergon 6bbf79a140 dm mpath: fix NULL pointer dereference when path parameters missing
multipath_ctr() forgets to return an error after detecting
missing path parameters.  Fix this.

Signed-off-by: Patrick LoPresti <lopresti@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-12 04:13:49 +01:00
Nikanth Karthikesan 8215d6ec5f dm table: remove unused dm_get_device range parameters
Remove unused parameters(start and len) of dm_get_device()
and fix the callers.

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-03-06 02:32:27 +00:00
Kiyoshi Ueda fb61264297 dm mpath: refactor pg_init
This patch pulls the pg_init path activation code out of
process_queued_ios() into a new function.

No functional change.

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>
2010-03-06 02:32:18 +00:00
Kiyoshi Ueda 2bded7bd7e dm mpath: wait for pg_init completion when suspending
When suspending the device we must wait for all I/O to complete, but
pg-init may be still in progress even after flushing the workqueue
for kmpath_handlerd in multipath_postsuspend.

This patch waits for pg-init completion correctly in
multipath_postsuspend().

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>
2010-03-06 02:32:13 +00:00
Kiyoshi Ueda d0259bf0ee 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>
2010-03-06 02:30:02 +00:00
Kiyoshi Ueda fce323dd68 dm mpath: avoid storing private suspended state
'suspended' flag in struct multipath was introduced to check whether
the multipath target is in suspended state, but the same check is
done through dm_suspended() now, so remove the flag and related code.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-03-06 02:29:59 +00:00
Moger, Babu f7b934c812 dm mpath: skip activate_path for failed paths
This patch adds two minor fixes while processing device mapper path activation.

Skip failed paths while calling activate_path.  If the path is already failed
then activate_path will fail for sure. We don't have to call in that case. In
some case this might cause prolonged retries unnecessarily.

Change the misleading message if the path being activated fails with SCSI_DH_NOSYS.

Signed-off-by: Babu Moger <babu.moger@lsi.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-03-06 02:29:49 +00:00
Moger, Babu 83c0d5d538 dm mpath: pass struct pgpath to pg init done
This patch removes some unnecessary argument casting. There is no
functional change with this patch.

Passes 'struct pgpath' through to pg_init_done() instead of the enclosed
'struct dm_path'.

Tested the changes with LSI storage..

CC: Chandra Seetharaman <chandra.seetharaman@us.ibm.com>
Signed-off-by: Babu Moger <babu.moger@lsi.com>
Acked-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-03-06 02:29:45 +00:00
Kiyoshi Ueda c2f3d24b78 dm mpath: reject messages when device is suspended
This patch rejects messages that can generate I/O while the device
itself is suspended.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Cc: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-12-10 23:52:27 +00:00
Mike Anderson 67a46dad25 dm mpath: prevent io from work queue while suspended
Reject messages that can generate I/O while the device itself
is suspended.

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Acked-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-12-10 23:52:21 +00:00
Mike Anderson 6380f26f04 dm mpath: add mutex to synchronize adding and flushing work
Add a mutex to allow possible creators of new work to synchronize with
flushing work queues.

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Acked-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-12-10 23:52:21 +00:00
Kiyoshi Ueda 6df400ab64 dm mpath: flush workqueues before suspend completes
This patch stops the remaining dm-mpath activity during the suspend
sequence by flushing workqueues in postsuspend function.

The current dm-mpath target may not be quiet even after suspend completes
because some workqueues (e.g. device_handler's work, event handling)
are not flushed during the suspend sequence, even though suspended
devices/targets are supposed to be quiet in this state.

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>
2009-12-10 23:52:19 +00:00
Chandra Seetharaman 3ae31f6a7b [SCSI] scsi_dh: Change the scsidh_activate interface to be asynchronous
Make scsi_dh_activate() function asynchronous, by taking in two additional
parameters, one is the callback function and the other is the data to call
the callback function with.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:00:46 -06:00