pm24.git/drivers/md/Kconfig, branch v3.8

dm thin: move bio_prison code to separate module

2012-10-12T20:02:13Z

The bio prison code will be useful to other future DM targets so move it to a separate module. Signed-off-by: Mike Snitzer Signed-off-by: Joe Thornber Signed-off-by: Alasdair G Kergon

Merge tag 'md-3.6' of git://neil.brown.name/md

2012-08-02T18:34:40Z

Pull additional md update from NeilBrown: "This contains a few patches that depend on plugging changes in the block layer so needed to wait for those. It also contains a Kconfig fix for the new RAID10 support in dm-raid." * tag 'md-3.6' of git://neil.brown.name/md: md/dm-raid: DM_RAID should select MD_RAID10 md/raid1: submit IO from originating thread instead of md thread. raid5: raid5d handle stripe in batch way raid5: make_request use batch stripe release

md/dm-raid: DM_RAID should select MD_RAID10

2012-08-01T22:35:43Z

Now that DM_RAID supports raid10, it needs to select that code to ensure it is included. Cc: Jonathan Brassow Reported-by: Fengguang Wu Signed-off-by: NeilBrown

dm persistent data: remove debug space map checker

2012-07-27T14:07:58Z

Remove debug space map checker from dm persistent data. The space map checker is a wrapper for other space maps that double checks the reference counts are correct. It holds all these reference counts in memory rather than on disk, so uses a lot of memory and is thus restricted to small pools. As yet, this checker hasn't found any issues, but has caused a few of its own due to people turning it on by default with larger pools. Removing. Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer Signed-off-by: Alasdair G Kergon

dm: add verity target

2012-03-28T17:43:38Z

This device-mapper target creates a read-only device that transparently validates the data on one underlying device against a pre-generated tree of cryptographic checksums stored on a second device. Two checksum device formats are supported: version 0 which is already shipping in Chromium OS and version 1 which incorporates some improvements. Signed-off-by: Mikulas Patocka Signed-off-by: Mandeep Singh Baines Signed-off-by: Will Drewry Signed-off-by: Elly Jones Cc: Milan Broz Cc: Olof Johansson Cc: Steffen Klassert Cc: Andrew Morton Signed-off-by: Alasdair G Kergon

dm raid: no longer experimental

2012-03-28T17:41:24Z

The dm raid module (using md) is becoming the preferred way of creating long-lived mirrors through userspace LVM so remove the EXPERIMENTAL tag. Signed-off-by: Alasdair G Kergon

dm uevent: no longer experimental

2012-03-28T17:41:24Z

Drop EXPERIMENTAL tag from dm-uevent. It's not changed for a while and some userspace tools are relying upon it. Signed-off-by: Alasdair G Kergon

dm: add thin provisioning target

2011-10-31T20:21:18Z

Initial EXPERIMENTAL implementation of device-mapper thin provisioning with snapshot support. The 'thin' target is used to create instances of the virtual devices that are hosted in the 'thin-pool' target. The thin-pool target provides data sharing among devices. This sharing is made possible using the persistent-data library in the previous patch. The main highlight of this implementation, compared to the previous implementation of snapshots, is that it allows many virtual devices to be stored on the same data volume, simplifying administration and allowing sharing of data between volumes (thus reducing disk usage). Another big feature is support for arbitrary depth of recursive snapshots (snapshots of snapshots of snapshots ...). The previous implementation of snapshots did this by chaining together lookup tables, and so performance was O(depth). This new implementation uses a single data structure so we don't get this degradation with depth. For further information and examples of how to use this, please read Documentation/device-mapper/thin-provisioning.txt Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer Signed-off-by: Alasdair G Kergon

dm: add bufio

2011-10-31T20:19:09Z

The dm-bufio interface allows you to do cached I/O on devices, holding recently-read blocks in memory and performing delayed writes. We don't use buffer cache or page cache already present in the kernel, because: * we need to handle block sizes larger than a page * we can't allocate memory to perform reads or we'd have deadlocks Currently, when a cache is required, we limit its size to a fraction of available memory. Usage can be viewed and changed in /sys/module/dm_bufio/parameters/ . The first user is thin provisioning, but more dm users are planned. Signed-off-by: Mikulas Patocka Signed-off-by: Alasdair G Kergon

dm raid: support metadata devices

2011-08-02T11:32:07Z

Add the ability to parse and use metadata devices to dm-raid. Although not strictly required, without the metadata devices, many features of RAID are unavailable. They are used to store a superblock and bitmap. The role, or position in the array, of each device must be recorded in its superblock. This is to help with fault handling, array reshaping, and sanity checks. RAID 4/5/6 devices must be loaded in a specific order: in this way, the 'array_position' field helps validate the correctness of the mapping when it is loaded. It can be used during reshaping to identify which devices are added/removed. Fault handling is impossible without this field. For example, when a device fails it is recorded in the superblock. If this is a RAID1 device and the offending device is removed from the array, there must be a way during subsequent array assembly to determine that the failed device was the one removed. This is done by correlating the 'array_position' field and the bit-field variable 'failed_devices'. Signed-off-by: Jonathan Brassow Signed-off-by: Alasdair G Kergon