This patch adds retries to the hp hardware handler, and utilizes the
MP_RETRY flag of dm-multipath. For now in the hp handler, if we get a
pg_init completed with a check condition we just assume we can retry the
pg_init command. We make this assumption because of incomplete data on
specific check condition code of the HP hardware, and because testing
has shown the HP path initialization command to be idempotent.
The number of times we retry is settable via the "pg_init_retries"
multipath map feature.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Acked-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch adds the most basic dm-multipath hardware support for the
HP active/passive arrays.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Acked-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch allows a failed path group initialisation command to be retried.
It adds a generic MP_RETRY flag and a "pg_init_retries" feature to
device-mapper multipath which limits the number of retries.
1. A hw handler sends a path initialization command to the storage and
the command completes with an error code indicating the command
should be retried.
2. The hardware handler calls dm_pg_init_complete() with MP_RETRY
set in err_flags to ask the dm multipath core to retry.
3. If the retry limit has not been exceeded, pg_init() is retried.
Otherwise fail_path() is called.
If you are using the userspace multipath-tools or device-mapper-multipath
package, you can set pg_init_retries in the 'device' section of your
/etc/multipath.conf file. For example:
features "2 pg_init_retries 7"
The number of PG retries attempted is reported in the 'dmsetup status' output.
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Acked-by: Mike Christie <michaelc@cs.wisc.edu>
Acked-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Replace numbers with names in labels in error paths, to avoid confusion
when new one get added between existing ones.
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Clean up, convert some spaces to tabs.
No functional change here.
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Add post-processing queue (per crypt device) for read operations.
Current implementation uses only one queue for all operations
and this can lead to starvation caused by many requests waiting
for memory allocation. But the needed memory-releasing operation
is queued after these requests (in the same queue).
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Use a separate single-threaded workqueue for each crypt device
instead of one global workqueue.
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove BIO_LIST and DEFINE_BIO_LIST macros that gain us nothing
since contents are initialised to NULL.
Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
In drivers/md/dm-ioctl.c::copy_params() there's a call to vmalloc()
where we currently cast the return value, but that's pretty pointless
given that vmalloc() returns "void *".
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Use bio_io_error() in only two places and tidy the code,
preparing for later patches.
There is no functional change in this patch.
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Kcopyd uses a semaphore as mutex. Use the mutex API instead of the (binary)
semaphore,
Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Replacing n & (n - 1) for power of 2 check by is_power_of_2(n)
Signed-off-by: vignesh babu <vignesh.babu@wipro.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch fixes a bd_mount_sem counter corruption bug in device-mapper.
thaw_bdev() should be called only when freeze_bdev() was called for the
device.
Otherwise, thaw_bdev() will up bd_mount_sem and corrupt the semaphore counter.
struct block_device with the corrupted semaphore may remain in slab cache
and be reused later.
Attached patch will fix it by calling unlock_fs() instead.
unlock_fs() will determine whether it should call thaw_bdev()
by checking the device is frozen or not.
Easy reproducer is:
#!/bin/sh
while [ 1 ]; do
dmsetup --notable create a
dmsetup --nolockfs suspend a
dmsetup remove a
done
It's not easy to see the effect of corrupted semaphore.
So I have tested with putting printk below in bdev_alloc_inode():
if (atomic_read(&ei->bdev.bd_mount_sem.count) != 1)
printk(KERN_DEBUG "Incorrect semaphore count = %d (%p)\n",
atomic_read(&ei->bdev.bd_mount_sem.count),
&ei->bdev);
Without the patch, I saw something like:
Incorrect semaphore count = 17 (f2ab91c0)
With the patch, the message didn't appear.
The bug was introduced in 2.6.16 with this bug fix:
commit d9dde59ba0
Date: Fri Feb 24 13:04:24 2006 -0800
[PATCH] dm: missing bdput/thaw_bdev at removal
Need to unfreeze and release bdev otherwise the bdev inode with
inconsistent state is reused later and cause problem.
and backported to 2.6.15.5.
It occurs only in free_dev(), which is called only when the dm device is
removed. The buggy code is executed only if md->suspended_bdev is
non-NULL and that can happen only when the device was suspended without
noflush.
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: stable@kernel.org
Fix missing space in dm-delay target status output
if separate read and write delay are configured.
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Add a missing 'dm_put_device' in an error path in crypt target constructor.
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Make size of dm_ioctl struct always 312 bytes on all supported
architectures.
This change retains compatibility with already-compiled code because
it uses an embedded offset to locate the payload that follows the
structure.
On 64-bit architectures there is no change at all; on 32-bit
we are increasing the size of dm-ioctl from 308 to 312 bytes.
Currently with 32-bit userspace / 64-bit kernel on x86_64
some ioctls (including rename, message) are incorrectly rejected
by the comparison against 'param + 1'. This breaks userspace
lvrename and multipath 'fail_if_no_path' changes, for example.
(BTW Device-mapper uses its own versioning and ignores the ioctl
size bits. Only the generic ioctl compat code on mixed arches
checks them, and that will continue to accept both sizes for now,
but we intend to list 308 as deprecated and eventually remove it.)
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: Guido Guenther <agx@sigxcpu.org>
Cc: Kevin Corry <kevcorry@us.ibm.com>
Cc: stable@kernel.org
Re-order the initialisation of dm-rdac to avoid registering the hw
handler before the workqueue has been initialised. Closes a race
that would potentially give an oops.
Signed-off-by: Bryn M. Reeves <breeves@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
If one compiles the example smount program, found in
Documentation/sharedsubtree.txt, with -Wall then there's a small
compiler warning rearing its ugly head :
smount.c: In function 'main':
smount.c:45: warning: implicit declaration of function 'strcmp'
Easily fixed by just including string.h
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Fix some grammar in the explanation of the Journal Block Device layer.
Signed-off-by: Shaun Zinck <shaun.zinck@gmail.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
This fixes a typo and rearranges the sentence to make more sense.
Signed-off-by: Shaun Zinck <shaun.zinck@gmail.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
These don't appear anywhere else in the kernel anymore.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Change the loop style of copy_data_pages() to remove a duplicate condition.
Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Update the file link in the Pegasus USB network driver's help text.
Signed-off-by: Cal Peake <cp@absolutedigital.net>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Update the maintainer of 2.4 kernel in Documentations/SubmittingPatches.
Signed-off-by: Li Yang <leo@zh-kernel.org>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
rcuref_inc_lf() is not used anymore. Replace it by atomic_inc_not_zero()
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Most of these fixes were already submitted for old kernel versions, and were
approved, but for some reason they never made it into the releases.
Because this is a consolidation of a couple old missed patches, it touches both
Kconfigs and documentation texts.
Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Spelling fixes in arch/um/.
Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Acked-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
