A static declaration missing.
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

This patch adds calls to dm_path_event for a failed path and a reinstated
path.
Signed-off-by: NMike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: NAlasdair 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: NDave Wysochanski <dwysocha@redhat.com>
Acked-by: NMike Christie <michaelc@cs.wisc.edu>
Acked-by: NChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

As bi_end_io is only called once when the reqeust is complete,
the 'size' argument is now redundant.  Remove it.

Now there is no need for bio_endio to subtract the size completed
from bi_size.  So don't do that either.

While we are at it, change bi_end_io to return void.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

This patch causes device-mapper to reject any barrier requests.  This is done
since most of the targets won't handle this correctly anyway.  So until the
situation improves it is better to reject these requests at the first place.
Since barrier requests won't get to the targets, the checks there can be
removed.

Cc: stable@kernel.org
Signed-off-by: NStefan Bader <shbader@de.ibm.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove explicit module name from messages as the macro now includes it
automatically.
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use new KMEM_CACHE() macro and make the newly-exposed structure names more
meaningful.  Also remove some superfluous casts and inlines (let a modern
compiler be the judge).
Acked-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Make the mapped device structure accessible to hardware handlers so error
messages can include the device name.
Signed-off-by: NEdward Goggin <egoggin@emc.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Implement the pushback feature for the multipath target.

The pushback request is used when:
  1) there are no valid paths;
  2) queue_if_no_path was set;
  3) a suspend is being issued with the DMF_NOFLUSH_SUSPENDING flag.
     Otherwise bios are returned to applications with -EIO.

To check whether queue_if_no_path is specified or not, you need to check
both queue_if_no_path and saved_queue_if_no_path, because presuspend saves
the original queue_if_no_path value to saved_queue_if_no_path.

The check for 1 already exists in both map_io() and do_end_io().
So this patch adds __must_push_back() to check 2 and 3.

Test results:
See the test results in the preceding patch.
Signed-off-by: NKiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Cc: dm-devel@redhat.com
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Update existing targets to use the new symbols for return values from target
map and end_io functions.

There is no effect on behaviour.

Test results:
Done build test without errors.
Signed-off-by: NKiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Cc: dm-devel@redhat.com
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NJosef Sipek <jsipek@fsl.cs.sunysb.edu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Rename DM's struct path to struct dm_path to prevent name collision between it
and struct path from fs/namei.c.
Signed-off-by: NJosef "Jeff" Sipek <jsipek@cs.sunysb.edu>
Acked-by: NAlasdair G Kergon <agk@redhat.com>
Cc: <reiserfs-dev@namesys.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Replace all uses of kmem_cache_t with struct kmem_cache.

The patch was generated using the following script:

	#!/bin/sh
	#
	# Replace one string by another in all the kernel sources.
	#

	set -e

	for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
		quilt add $file
		sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
		mv /tmp/$$ $file
		quilt refresh
	done

The script was run like this

	sh replace kmem_cache_t "struct kmem_cache"
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix up for make allyesconfig.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>

Use kzalloc() instead of kmalloc() + memset().
Signed-off-by: NMicha³ Miros³aw <mirq-linux@rere.qmqm.pl>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

After initialising m->ti, there's no need to pass it in subsequent calls to
static functions used for parsing parameters.
Signed-off-by: NMicha³ Miros³aw <mirq-linux@rere.qmqm.pl>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The new ioctl code passes the wrong file pointer to the underlying device.
No file pointer is available so make a temporary fake one.

ioctl_by_bdev() does set_fs(KERNEL_DS) so it's for ioctls originating
within the kernel and unsuitable here.  We are processing ioctls that
originated in userspace and mapping them to different devices.  Fixing the
existing callers that pass a NULL file struct and consolidating the
fake_file users are separate matters to solve in later patches.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Export blkdev_driver_ioctl for device-mapper.

If we get as far as the device-mapper ioctl handler, we know the ioctl is not
a standard block layer BLK* one, so we don't need to check for them a second
time and can call blkdev_driver_ioctl() directly.
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

When an ioctl is performed on a multipath device simply pass it on to the
underlying block device through current_path.  If current path is not yet
selected, select it.
Signed-off-by: NMilan Broz <mbroz@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix BUG I tripped on while testing failover and multipathing.

BUG shows up on error path in multipath_ctr() when parse_priority_group()
fails after returning at least once without error.  The fix is to
initialize m->ti early - just after alloc()ing it.

BUG: unable to handle kernel NULL pointer dereference at virtual address 00000000
 printing eip:
c027c3d2
*pde = 00000000
Oops: 0000 [#3]
Modules linked in: qla2xxx ext3 jbd mbcache sg ide_cd cdrom floppy
CPU:    0
EIP:    0060:[<c027c3d2>]    Not tainted VLI
EFLAGS: 00010202   (2.6.17.3 #1)
EIP is at dm_put_device+0xf/0x3b
eax: 00000001   ebx: ee4fcac0   ecx: 00000000   edx: ee4fcac0
esi: ee4fc4e0   edi: ee4fc4e0   ebp: 00000000   esp: c5db3e78
ds: 007b   es: 007b   ss: 0068
Process multipathd (pid: 15912, threadinfo=c5db2000 task=ef485a90)
Stack: ec4eda40 c02816bd ee4fc4c0 00000000 f7e89498 f883e0bc c02816f6 f7e89480
       f7e8948c c0281801 ffffffea f7e89480 f883e080 c0281ffe 00000001 00000000
       00000004 dfe9cab8 f7a693c0 f883e080 f883e0c0 ca4b99c0 c027c6ee 01400000
Call Trace:
 <c02816bd> free_pgpaths+0x31/0x45  <c02816f6> free_priority_group+0x25/0x2e
 <c0281801> free_multipath+0x35/0x67  <c0281ffe> multipath_ctr+0x123/0x12d
 <c027c6ee> dm_table_add_target+0x11e/0x18b  <c027e5b4> populate_table+0x8a/0xaf
 <c027e62b> table_load+0x52/0xf9  <c027ec23> ctl_ioctl+0xca/0xfc
 <c027e5d9> table_load+0x0/0xf9  <c0152146> do_ioctl+0x3e/0x43
 <c0152360> vfs_ioctl+0x16c/0x178  <c01523b4> sys_ioctl+0x48/0x60
 <c01029b3> syscall_call+0x7/0xb
Code: 97 f0 00 00 00 89 c1 83 c9 01 80 e2 01 0f 44 c1 88 43 14 8b 04 24 59 5b 5e 5f 5d c3 53 89 c1 89 d3 ff 4a 08 0f 94 c0 84 c0 74 2a <8b> 01 8b 10 89 d8 e8 f6 fb ff ff 8b 03 8b 53 04 89 50 04 89 02
EIP: [<c027c3d2>] dm_put_device+0xf/0x3b SS:ESP 0068:c5db3e78
Signed-off-by: NMichal Miroslaw <mirq-linux@rere.qmqm.pl>
Acked-by: NAlasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Tidy device-mapper error messages to include context information
automatically.
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Modify well over a dozen mempool users to call mempool_create_slab_pool()
rather than calling mempool_create() with extra arguments, saving about 30
lines of code and increasing readability.
Signed-off-by: NMatthew Dobson <colpatch@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

do_end_io() can be called without interrupts blocked.
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

When creating a multipath device, if the queue_if_no_path parameter is
specified it gets ignored.

While the queue_if_no_path variable is correctly set to 1, the
saved_queue_if_no_path gets set to 0.  When the device is subsequently made
live (resumed), the saved value (0) always overwrites the live value (1) so
the option *always* gets turned off.

The fix adds a parameter to the queue_if_no_path() function to indicate
whether the previous value should be preserved or not - if not, as when the
device is being set up, the saved value is set to the new value (1).
Signed-Off-By: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Prevent more than one priority group initialisation function from being
outstanding at once.  Otherwise the completion functions interfere with each
other.  Also, reloading the table could reference a freed pointer.

Only reset queue_io in pg_init_complete if another pg_init isn't required.
Skip process_queued_ios if the queue is empty so that we only trigger a
pg_init if there's I/O.
Signed-off-by: NLars Marowsky-Bree <lmb@suse.de>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

To avoid deadlock when suspending a multipath device after all its paths have
failed, stop queueing any I/O that is about to fail *before* calling
freeze_bdev instead of after.

Instead of setting a multipath 'suspended' flag which would have to be reset
if an error occurs during the process, save the previous queueing state and
leave userspace to restore if it wishes.
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The multipath destructor must flush its workqueue.  Otherwise items that
reference the destroyed object could remain.

From: "goggin, edward" <egoggin@emc.com>
Signed-off-by: NLars Marowsky-Bree <lmb@suse.de>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

dm multipath will report barriers as not supported with this patch.
Signed-off-by: NLars Marowsky-Bree <lmb@suse.de>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

READA errors failing with EWOULDBLOCK/EAGAIN do not constitute a valid
reason for failing the path; this lead to erratic errors on DM multipath
devices.  This error can be safely propagated upwards without failing the
path.
Acked-by: NKevin Corry <kevcorry@us.ibm.com>
Acked-by: NJens Axboe <axboe@suse.de>
Signed-off-by: NLars Marowsky-Bree <lmb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

dm-mpath.c needs to use a private workqueue (like other dm targets already do)
to avoid interfering with users of the default workqueue.
Signed-Off-By: NAlasdair G Kergon <agk@redhat.com>
Acked-by: NJens Axboe <axboe@suse.de>
Signed-off-by: NLars Marowsky-Bree <lmb@suse.de>
Signed-off-by: <mikenc@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!