This patch contains a device-mapper mirror log module that forwards
requests to userspace for processing.
The structures used for communication between kernel and userspace are
located in include/linux/dm-log-userspace.h. Due to the frequency,
diversity, and 2-way communication nature of the exchanges between
kernel and userspace, 'connector' was chosen as the interface for
communication.
The first log implementations written in userspace - "clustered-disk"
and "clustered-core" - support clustered shared storage. A userspace
daemon (in the LVM2 source code repository) uses openAIS/corosync to
process requests in an ordered fashion with the rest of the nodes in the
cluster so as to prevent log state corruption. Other implementations
with no association to LVM or openAIS/corosync, are certainly possible.
(Imagine if two machines are writing to the same region of a mirror.
They would both mark the region dirty, but you need a cluster-aware
entity that can handle properly marking the region clean when they are
done. Otherwise, you might clear the region when the first machine is
done, not the second.)
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Currently, device-mapper maintains a separate instance of 'struct
queue_limits' for each table of each device. When the configuration of
a device is to be changed, first its table is loaded and this structure
is populated, then the device is 'resumed' and the calculated
queue_limits are applied.
This places restrictions on how userspace may process related devices,
where it is often advantageous to 'load' tables for several devices
at once before 'resuming' them together. As the new queue_limits
only take effect after the 'resume', if they are changing and one
device uses another, the latter must be 'resumed' before the former
may be 'loaded'.
This patch moves the calculation of these queue_limits out of
the 'load' operation into 'resume'. Since we are no longer
pre-calculating this struct, we no longer need to maintain copies
within our dm structs.
dm_set_device_limits() now passes the 'start' of the device's
data area (aka pe_start) as the 'offset' to blk_stack_limits().
init_valid_queue_limits() is replaced by blk_set_default_limits().
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: martin.petersen@oracle.com
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
create_log_context() must use the logical_block_size from the log disk,
where the I/O happens, not the target's logical_block_size.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Add .iterate_devices to 'struct target_type' to allow a function to be
called for all devices in a DM target. Implemented it for all targets
except those in dm-snap.c (origin and snapshot).
(The raid1 version number jumps to 1.12 because we originally reserved
1.1 to 1.11 for 'block_on_error' but ended up using 'handle_errors'
instead.)
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: martin.petersen@oracle.com
Copy the table's queue_limits to the DM device's request_queue. This
properly initializes the queue's topology limits and also avoids having
to track the evolution of 'struct queue_limits' in
dm_table_set_restrictions()
Also fixes a bug that was introduced in dm_table_set_restrictions() via
commit ae03bf639a. In addition to
establishing 'bounce_pfn' in the queue's limits blk_queue_bounce_limit()
also performs an allocation to setup the ISA DMA pool. This allocation
resulted in "sleeping function called from invalid context" when called
from dm_table_set_restrictions().
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Use blk_stack_limits() to stack block limits (including topology) rather
than duplicate the equivalent within Device Mapper.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Impose necessary and sufficient conditions on a devices's table such
that any incoming bio which respects its logical_block_size can be
processed successfully.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Ensure I/O is aligned to the logical block size of target devices.
Rename check_device_area() to device_area_is_valid() for clarity and
establish the device limits including the logical block size prior to
calling it.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Add support for passing a 32 bit "cookie" into the kernel with the
DM_SUSPEND, DM_DEV_RENAME and DM_DEV_REMOVE ioctls. The (unsigned)
value of this cookie is returned to userspace alongside the uevents
issued by these ioctls in the variable DM_COOKIE.
This means the userspace process issuing these ioctls can be notified
by udev after udev has completed any actions triggered.
To minimise the interface extension, we pass the cookie into the
kernel in the event_nr field which is otherwise unused when calling
these ioctls. Incrementing the version number allows userspace to
determine in advance whether or not the kernel supports the cookie.
If the kernel does support this but userspace does not, there should
be no impact as the new variable will just get ignored.
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Add a file named 'suspended' to each device-mapper device directory in
sysfs. It holds the value 1 while the device is suspended. Otherwise
it holds 0.
Signed-off-by: Peter Rajnoha <prajnoha@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Report any devices forgotten to be freed before a table is destroyed.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch adds a service time oriented dynamic load balancer,
dm-service-time, which selects the path with the shortest estimated
service time for the incoming I/O.
The service time is estimated by dividing the in-flight I/O size
by a performance value of each path.
The performance value can be given as a table argument at the table
loading time. If no performance value is given, all paths are
considered equal.
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>
This patch adds a dynamic load balancer, dm-queue-length, which
balances the number of in-flight I/Os across the paths.
The code is based on the patch posted by Stefan Bader:
https://www.redhat.com/archives/dm-devel/2005-October/msg00050.html
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
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>
This patch makes two additions to the dm path selector interface for
dynamic load balancers:
o a new hook, start_io()
o a new parameter 'nr_bytes' to select_path()/start_io()/end_io()
to pass the size of the I/O
start_io() is called when a target driver actually submits I/O
to the selected path.
Path selectors can use it to start accounting of the I/O.
(e.g. counting the number of in-flight I/Os.)
The start_io hook is based on the patch posted by Stefan Bader:
https://www.redhat.com/archives/dm-devel/2005-October/msg00050.html
nr_bytes, the size of the I/O, is so path selectors can take the
size of the I/O into account when deciding which path to use.
dm-service-time uses it to estimate service time, for example.
(Added the nr_bytes member to dm_mpath_io instead of using existing
details.bi_size, since request-based dm patch deletes it.)
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
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>
Send barrier requests when updating the exception area.
Exception area updates need to be ordered w.r.t. data writes, so that
the writes are not reordered in hardware disk cache.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
If -EOPNOTSUPP was returned and the request was a barrier request, retry it
without barrier.
Retry all regions for now. Barriers are submitted only for one-region requests,
so it doesn't matter. (In the future, retries can be limited to the actual
regions that failed.)
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Add another field, eopnotsupp_bits. It is subset of error_bits, representing
regions that returned -EOPNOTSUPP. (The bit is set in both error_bits and
eopnotsupp_bits).
This value will be used in further patches.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Flush support for dm-snapshot target.
This patch just forwards the flush request to either the origin or the snapshot
device. (It doesn't flush exception store metadata.)
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Flush support for the stripe target.
This sets ti->num_flush_requests to the number of stripes and
remaps individual flush requests to the appropriate stripe devices.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Pass empty barrier flushes to the targets in dm_flush().
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Introduce num_flush_requests for a target to set to say how many flush
instructions (empty barriers) it wants to receive. These are sent by
__clone_and_map_empty_barrier with map_info->flush_request going from 0
to (num_flush_requests - 1).
Old targets without flush support won't receive any flush requests.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove the check that the size of the cloned bio is not zero because a
subsequent patch needs to send zero-sized barriers down this path.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
If the underlying device doesn't support barriers and dm receives a
barrier, it waits until all requests on that device drain so it no
longer needs to report -EOPNOTSUPP to the caller.
This patch deals with the confusing situation when moving a volume from
one physical device to another triggers an EOPNOTSUPP on a volume that
didn't report it before.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
With the following patches, more than one error can occur during
processing. Change md->barrier_error so that only the first one is
recorded and returned to the caller.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
If barrier request was returned with DM_ENDIO_REQUEUE,
requeue it in dm_wq_work instead of dec_pending.
This allows us to correctly handle a situation when some targets
are asking for a requeue and other targets signal an error.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Make dm_flush return void.
The first error during flush is stored in md->barrier_error instead.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Fix a potential deadlock when creating multiple snapshots by holding a
reference to struct block_device for the whole lifecycle of every dm
device instead of obtaining it independently at each point it is needed.
bdget_disk() was called while the device was being suspended, in
dm_suspend(). However there could be other devices already suspended,
for example when creating additional snapshots of a device. bdget_disk()
can wait for IO and allocate memory resulting in waiting for the
already-suspended device - deadlock.
This patch changes the code so that it gets the reference to struct
block_device when struct mapped_device is allocated and initialized in
alloc_dev() where it is always OK to allocate memory or wait for I/O.
It drops the reference when it is destroyed in free_dev(). Thus there
is no call to bdget_disk() while any device is suspended.
Previously unlock_fs() was called only if bdev was held. Now it is
called unconditionally, but the superfluous calls are harmless because
it returns immediately if the filesystem was not previously frozen.
This patch also now allows the device size to be changed in a
noflush suspend because the bdev is held. This has no adverse effect.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Rename suspended_bdev to bdev.
This patch doesn't change any functionality, just renames the variable.
In the next patch, the variable will be used even for non-suspended device.
(Pre-requisite for the per-target barrier support patches.)
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
When snapshots are created using 'p' instead of 'P' as the
exception store type, the device-mapper table loading fails.
This patch makes the code case insensitive as intended and fixes some
regressions reported with device-mapper snapshots.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Use i_size_read() instead of reading i_size.
If someone changes the size of the device simultaneously, i_size_read
is guaranteed to return a valid value (either the old one or the new one).
i_size can return some intermediate invalid value (on 32-bit computers
with 64-bit i_size, the reads to both halves of i_size can be interleaved
with updates to i_size, resulting in garbage being returned).
Cc: stable@kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
A bio that has two or more vector entries, size less than or equal to
page size, that crosses a stripe boundary of an underlying md device is
accepted by device mapper (it conforms to all its limits) but not by the
underlying device.
The fix is: If device mapper selects the one-page maximum request size,
it also needs to set its own q->merge_bvec_fn to reject any bios with
multiple vector entries that span more pages.
The problem was discovered in the following scenario:
* MD - RAID-0
* LV on the top of it (raid1, snapshot or striped with chunk
size/stripe larger than RAID-0 stripe)
* one of the logical volumes is exported to xen domU
* inside xen domU it is partitioned, the key point is that the partition
must be unaligned on page boundary (fdisk normally aligns the partition to
63 sectors which will trigger it)
* install the system on the partitioned disk in domU
This causes I/O failures in dom0.
Reference: https://bugzilla.redhat.com/show_bug.cgi?id=223947
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The commit fe9cf30eb8 moves dm table event
submission from kmultipath queue to kernel kevent queue to avoid a
deadlock.
There is a possibility of race condition because kevent queue is not flushed
in the multipath destructor. The scenario is:
- some event happens and is queued to keventd
- keventd thread is delayed due to scheuling latency or some other work
- multipath device is destroyed
- keventd now attempts to process work_struct that is residing in already
released memory.
The patch flushes the keventd queue in multipath constructor.
I've already fixed similar bug in dm-raid1.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: stable@kernel.org
If the code can't handle allocation failures, use __GFP_NOFAIL so that
in case of memory pressure the allocator will retry indefinitely and
won't return NULL which would cause a crash in the function.
This is still not a correct fix, it may cause a classic deadlock when
memory manager waits for I/O being done and I/O waits for some free memory.
I/O code shouldn't allocate any memory. But in this case it probably
doesn't matter much in practice, people usually do not swap on RAID.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Fixed a problem affecting reinstatement of passive paths.
Before we moved the hardware handler from dm to SCSI, it performed a pg_init
for a path group and didn't maintain any state about each path in hardware
handler code.
But in SCSI dh, such state is now maintained, as we want to fail I/O early on a
path if it is not the active path.
All the hardware handlers have a state now and set to active or some form of
inactive. They have prep_fn() which uses this state to fail the I/O without
it ever being sent to the device.
So in effect when dm-multipath calls scsi_dh_activate(), activate is
sent to only one path and the "state" of that path is changed appropriately
to "active" while other paths in the same path group are never changed
as they never got an "activate".
In order make sure all the paths in a path group gets their state set
properly when a pg_init happens, we need to call scsi_dh_activate() on
all paths in a path group.
Doing this at the hardware handler layer is not a good option as we
want the multipath layer to define the relationship between path and path
groups and not the hardware handler.
Attached patch sends an "activate" on each path in a path group when a
path group is switched. It also sends an activate when a path is reinstated.
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
When specifying a different hardware handler via multipath
features we should be able to override the built-in defaults.
The problem here is the hardware table from scsi_dh is compiled
in and cannot be changed from userland. The multipath.conf OTOH
is purely user-defined and, what's more, the user might have a valid
reason for modifying it.
(EG EMC Clariion can well be run in PNR mode even though ALUA is
active, or the user might want to try ALUA on any as-of-yet unknown
devices)
So _not_ allowing multipath to override the device handler setting
will just add to the confusion and makes error tracking even more
difficult.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Do not process sysfs attributes when device is being destroyed.
Otherwise code can cause
BUG_ON(test_bit(DMF_FREEING, &md->flags));
in dm_put() call.
Cc: stable@kernel.org
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
When decoding (N)RPN sequencer events into raw MIDI commands, the
extra_decode_xrpn() function had accidentally swapped the MSB and LSB
controller values of both the parameter number and the data value.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: <stable@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Add the digital-mic support with ALC262 auto model.
The new ALC262 models have the digital mic at NID 0x12. This widget
isn't checked in the current alc262_auto_create_analog_input_ctls()
since it's under 0x18. So, just reuse the routine for alc269 to fix
the behavior.
But, it doesn't suffice: the digital mic is supported only with the
ADC0, we have to exclude other ADCs when d-mic is detected.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Fix the check of the input-source type by checking the widget type of
each capture-source item. Since some codecs can have both the mixer
and selector types depending on the ADC, alc_mux_enum_put() needs to
check each widget.
With this change, spec->capture_style gets unneeded, so it's removed,
too.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The commit f9e336f65b
ALSA: hda - Unify capture mixer creation in realtek codes
removed the "Input Source" mixer element creation for toshiba-s06 model
because it contains a digital-mic input.
This patch take the control back.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: <stable@kernel.org>
Fix the comparison of unsigned int that causes a compile warning below
by changing to the right signed type:
patch_sigmatel.c: In function ‘stac92xx_vref_set’:
patch_sigmatel.c:658: warning: comparison of unsigned expression < 0 is always false
Signed-off-by: Takashi Iwai <tiwai@suse.de>
There's a large 500ms delay in snd_via82xx_codec_wait() that, at least
on my hardware, appears to be unnecessary. The rest of the init of
the card works without logging any warnings or errors and both audio
and mixer settings work.
This adds an "nodelay" parameter to disable this (undocumented in the
code) large delay improving bootup time by 489-500ms.
[ 1.034217] initcall alsa_card_via82xx_init+0x0/0x16 returned 0 after 505757 usecs
vs.
[ 0.533136] initcall alsa_card_via82xx_init+0x0/0x16 returned 0 after 15915 usecs
Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Jonthan Brassow
Mike Snitzer
Milan Broz
Peter Rajnoha
Kiyoshi Ueda
Mikulas Patocka
Alasdair G Kergon
Chandra Seetharaman
Hannes Reinecke
Clemens Ladisch
Takashi Iwai
Simon Arlott