When a raid1 array is configured to support write-behind
on some devices, it normally only reads from other devices.
If all devices are write-behind (because the rest have failed)
it is possible for a read request to be serviced before a
behind-write request, which would appear as data corruption.
So when forced to read from a WriteMostly device, wait for any
write-behind to complete, and don't start any more behind-writes.
Signed-off-by: NeilBrown <neilb@suse.de>
This message seems to suggest the named device is the one on which a
read failed, however it is actually the device that the read will be
redirected to.
So make the message a little clearer.
Reported-by: Tim Burgess <ozburgess@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This is
- unnecessary because mddev_suspend is always followed by a call to
->stop, and each ->stop unregisters the thread, and
- a problem as it makes it awkwards to suspend and then resume a
device as we will want later.
Signed-off-by: NeilBrown <neilb@suse.de>
We used to pass the personality make_request function direct
to the block layer so the first argument had to be a queue.
But now we have the intermediary md_make_request so it makes
at lot more sense to pass a struct mddev_s.
It makes it possible to have an mddev without its own queue too.
Signed-off-by: NeilBrown <neilb@suse.de>
This moves the call to the other side of set_readonly, but that should
not be an issue.
This encapsulates in 'md_stop' all of the functionality for internally
stopping the array, leaving all the interactions with externalities
(sysfs, request_queue, gendisk) in do_md_stop.
Signed-off-by: NeilBrown <neilb@suse.de>
Using do_md_stop to set an array to read-only is a little confusing.
Now most of the common code has been factored out, split
md_set_readonly off in to a separate function.
Signed-off-by: NeilBrown <neilb@suse.de>
Further refactoring of do_md_stop.
This one requires some explanation as it takes code from different
places in do_md_stop, so some re-ordering happens.
We only get into this part of do_md_stop if there are no active opens
of the device, so no writes can be happening and the device must have
been flushed. In md_stop_writes we want to stop any internal sources
of writes - i.e. resync - and flush out the metadata.
The only code that was previously before some of this code is
code to clean up the queue, the mddev, the gendisk, or sysfs, all
of which is probably better after code that makes active changes (i.e.
triggers writes).
Signed-off-by: NeilBrown <neilb@suse.de>
do_md_stop is large and clunky, so hard to understand.
This is a first step of refactoring, pulling two simple
sub-functions out.
Signed-off-by: NeilBrown <neilb@suse.de>
As part of relaxing the binding between an mddev and gendisk,
we separate do_md_run into two functions.
md_run does all the work internal to md
do_md_run calls md_run and makes and changes to gendisk
that are required.
Signed-off-by: NeilBrown <neilb@suse.de>
We set ->changed to 1 and call check_disk_change at the end
of md_open so that bd_invalidated would be set and thus
partition rescan would happen appropriately.
Now that we call revalidate_disk directly, which sets bd_invalidates,
that indirection is no longer needed and can be removed.
Signed-off-by: NeilBrown <neilb@suse.de>
Using ->array_sectors rather than get_capacity() is more
direct and is a step towards relaxing the tight connection
between mddev and gendisk.
Signed-off-by: NeilBrown <neilb@suse.de>
While I generally prefer letting personalities do as much as possible,
given that we have a central md_make_request anyway we may as well use
it to simplify code.
Also this centralises knowledge of ->gendisk which will help later.
Signed-off-by: NeilBrown <neilb@suse.de>
Diving through ->queue to find mddev is unnecessarily complex - there
is an easier path to finding mddev, so use that.
Signed-off-by: NeilBrown <neilb@suse.de>
Level changes can be very significant, so make sure
to notify them via sysfs.
Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When metadata is being managed by user-space, md doesn't know
what the maximum number of devices allowed in an array is
so ->max_disks is 0. In this case we should allow any (+ve)
number of disks.
Signed-off-by: NeilBrown <neilb@suse.de>
Writing "none" to "../md/dev-xx/slot" removes that device
from being an active part of the array, but it didn't
set ->raid_disk to -1 to record this fact.
Signed-off-by: Maciej Trela <Maciej.Trela@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
In a subsequent patch we will make it possible to change
mddev->raid_disks while a RAID0 or RAID10 array is active. This is
part of the process of reshaping such an array.
This means that we cannot use this value while processes requests
(it is OK to use it during initialisation as we are locked against
changes then).
Both RAID0 and RAID10 have the same value stored in the private data
structure, so use that value instead.
Signed-off-by: NeilBrown <neilb@suse.de>
This was needed when sysfs files could only be 'notified'
from process context. Now that we have sys_notify_direct,
we can call it directly from an interrupt.
Signed-off-by: NeilBrown <neilb@suse.de>
void pointers do not need to be cast to other pointer types.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Keep track of the maximum number of concurrent write-behind requests
for an md array and exposed this number in sysfs at
md/bitmap/max_backlog_used
Writing any value to this file will clear it.
This allows userspace to be involved in tuning bitmap/backlog.
Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: NeilBrown <neilb@suse.de>
These fields have never been used.
commit 4b6d287f62
added them, but also added identical files to bitmap_super_s,
and only used the latter.
So remove these unused fields.
Signed-off-by: NeilBrown <neilb@suse.de>
There is a very small race window when writing to a
RAID1 such that if a device is marked faulty at exactly the wrong
time, the write-in-progress will not be sent to the device,
but the bitmap (if present) will be updated to say that
the write was sent.
Then if the device turned out to still be usable as was re-added
to the array, the bitmap-based-resync would skip resyncing that
block, possibly leading to corruption. This would only be a problem
if no further writes were issued to that area of the device (i.e.
that bitmap chunk).
Suitable for any pending -stable kernel.
Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
Some levels expect the 'redundancy group' to be present,
others don't.
So when we change level of an array we might need to
add or remove this group.
This requires fixing up the current practice of overloading ->private
to indicate (when ->pers == NULL) that something needs to be removed.
So create a new ->to_remove to fill that role.
When changing levels, we may need to add or remove attributes. When
changing RAID5 -> RAID6, we both add and remove the same thing. It is
important to catch this and optimise it out as the removal is delayed
until a lock is released, so trying to add immediately would cause
problems.
Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
When an array is stopped we need to remove some
sysfs files which are dependent on the type of array.
We need to delay that deletion as deleting them while holding
reconfig_mutex can lead to deadlocks.
We currently delay them until the array is completely destroyed.
However it is possible to deactivate and then reactivate the array.
It is also possible to need to remove sysfs files when changing level,
which can potentially happen several times before an array is
destroyed.
So we need to delete these files more promptly: as soon as
reconfig_mutex is dropped.
We need to ensure this happens before do_md_run can restart the array,
so we use open_mutex for some extra locking. This is not deadlock
prone.
Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
Since commit ef286f6fa6
it has been important that each personality clears
->private in the ->stop() function, or sets it to a
attribute group to be removed.
linear.c doesn't. This can sometimes lead to an oops,
though it doesn't always.
Suitable for 2.6.33-stable and 2.6.34.
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: stable@kernel.org
When the user sets the block device to readwrite then the mddev should
follow suit. Otherwise, the BUG_ON in md_write_start() will be set to
trigger.
The reverse direction, setting mddev->ro to match a set readonly
request, can be ignored because the blkdev level readonly flag precludes
the need to have mddev->ro set correctly. Nevermind the fact that
setting mddev->ro to 1 may fail if the array is in use.
Cc: <stable@kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
If a component device has a merge_bvec_fn then as we never call it
we must ensure we never need to. Currently this is done by setting
max_sector to 1 PAGE, however this does not stop a bio being created
with several sub-page iovecs that would violate the merge_bvec_fn.
So instead set max_segments to 1 and set the segment boundary to the
same as a page boundary to ensure there is only ever one single-page
segment of IO requested at a time.
This can particularly be an issue when 'xen' is used as it is
known to submit multiple small buffers in a single bio.
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: stable@kernel.org
* git://git.kernel.org/pub/scm/linux/kernel/git/amit/virtio-console:
virtio: console: Use better variable names for fill_queue operation
virtio: console: Fix type of 'len' as unsigned int
* 'for-linus/i2c' of git://git.fluff.org/bjdooks/linux:
i2c: Add support for Xilinx XPS IIC Bus Interface
i2c: omap: Add support for 16-bit registers
i2c-pnx: fix setting start/stop condition
powerpc: doc/dts-bindings: update doc of FSL I2C bindings
i2c-mpc: add support for the MPC512x processors from Freescale
i2c-mpc: rename "setclock" initialization functions to "setup"
i2c-mpc: use __devinit[data] for initialization functions and data
i2c/imx: don't add probe function to the driver struct
i2c: Add support for Ux500/Nomadik I2C controller
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (26 commits)
sh: Convert sh to use read/update_persistent_clock
sh: Move PMB debugfs entry initialization to later stage
sh: Fix up flush_cache_vmap() on SMP.
sh: fix up MMU reset with variable PMB mapping sizes.
sh: establish PMB mappings for NUMA nodes.
sh: check for existing mappings for bolted PMB entries.
sh: fixed virt/phys mapping helpers for PMB.
sh: make pmb iomapping configurable.
sh: reworked dynamic PMB mapping.
sh: Fix up cpumask_of_pcibus() for the NUMA build.
serial: sh-sci: Tidy up build warnings.
sh: Fix up ctrl_read/write stragglers in migor setup.
serial: sh-sci: Add DMA support.
dmaengine: shdma: extend .device_terminate_all() to record partial transfer
sh: merge sh7722 and sh7724 DMA register definitions
sh: activate runtime PM for dmaengine on sh7722 and sh7724
dmaengine: shdma: add runtime PM support.
dmaengine: shdma: separate DMA headers.
dmaengine: shdma: convert to platform device resources
dmaengine: shdma: fix DMA error handling.
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6:
parisc: use __ratelimit in unaligned.c
parisc: Convert to read/update_persistent_clock
parisc: Simplify param.h by including <asm-generic/param.h>
parisc: drop unnecessary cast in __ldcw_align() macro
parisc: add strict copy size checks (v2)
parisc: remove trailing space in messages
parisc: ditto sys_accept4
parisc: wire up sys_recvmmsg
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
PM: Provide generic subsystem-level callbacks
PM / Runtime: Document power.runtime_auto and related functions
This patch adds support for the Xilinx XPS IIC Bus Interface.
The driver uses the dynamic mode, supporting to put several
I2C messages in the FIFO to reduce the number of interrupts.
It has the same feature as ocores, it can be passed a list
of devices that will be added when the bus is probed.
Signed-off-by: Richard Röjfors <richard.rojfors@pelagicore.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
The current i2c-omap driver is set up for 32-bit registers, which
corresponds to most OMAP devices. However, OMAP730/850 based
devices use a 16-bit register size.
This change modifies the driver to perform a runtime CPU type check
to determine the register sizes, and uses a bit shift of either 1
or 2 bits to compute the proper register sizes for all registers.
Signed-off-by: Cory Maccarrone <darkstar6262@gmail.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
The start/stop condtions are set in different places repetedly in the i2c-pnx
driver. Beside in i2c_pnx_start and i2c_pnx_stop the start/stop bit are also
set during the transfer of a i2c message in the master_xmit/rcv calls. This is
wrong since we can't set the start/stop condition during the transaction of a
single message any way. As a matter of fact, the driver will sometimes set both
the start and the stop bits at one time. This can be easily reproduced by
sending a simple read request like e.g
struct i2c_msg msgs[] = {
{ addr, 0, 1, buf },
{ addr, I2C_M_RD, offset, buf }
};
While processing the first message the i2c_pnx_master_xmit will set both the
start_bit and the stop_bit, which will eventually confuse the slave.
Fixed by remove setting start/stop condition from the transmit routines.
Signed-off-by: Luotao Fu <l.fu@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
As I2C interrupts must be enabled for the MPC512x by the setup function
as well, "fsl,preserve-clocking" is handled in a slighly different way.
Also, the old settings are now reported calling dev_dbg(). For the
MPC512x the clock setup function of the MPC52xx can be re-used.
Furthermore, the Kconfig help has been updated and corrected.
Signed-off-by: Wolfgang Grandegger <wg@denx.de>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
To prepare support for the MPC512x processors from Freescale the
"setclock" initialization functions have been renamed to "setup"
because I2C interrupts must be enabled for the MPC512x by this
function as well.
Signed-off-by: Wolfgang Grandegger <wg@denx.de>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
"__devinit[data]" has not yet been used for all initialization functions
and data. To avoid truncating lines, the struct "mpc_i2c_match_data" has
been renamed to "mpc_i2c_data", which is even the better name.
Signed-off-by: Wolfgang Grandegger <wg@denx.de>
Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
