linux/drivers/md
Joe Thornber 2dd9c257fb dm thin: support read only external snapshot origins
Support the use of an external _read only_ device as an origin for a thin
device.

Any read to an unprovisioned area of the thin device will be passed
through to the origin.  Writes trigger allocation of new blocks as
usual.

One possible use case for this would be VM hosts that want to run
guests on thinly-provisioned volumes but have the base image on another
device (possibly shared between many VMs).

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-03-28 18:41:28 +01:00
..
persistent-data dm persistent data: remove space map ref_count entries if redundant 2012-03-28 18:41:27 +01:00
bitmap.c md updates for 3.4 2012-03-22 12:29:50 -07:00
bitmap.h md/bitmap: discard CHUNK_BLOCK_SHIFT macro 2012-03-19 12:46:41 +11:00
dm-bio-record.h dm: preserve bi_io_vec when resubmitting bios 2009-04-02 19:55:23 +01:00
dm-bufio.c dm-bufio.c: there's no need to include linux/version.h 2012-02-03 22:38:12 +01:00
dm-bufio.h dm: add bufio 2011-10-31 20:19:09 +00:00
dm-crypt.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-delay.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-exception-store.c dm exception store: fix init error path 2012-03-28 18:41:22 +01:00
dm-exception-store.h dm snapshot: test chunk size against both origin and snapshot 2010-08-12 04:13:51 +01:00
dm-flakey.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-io.c dm io: fix discard support 2012-03-07 19:09:37 +00:00
dm-ioctl.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-kcopyd.c dm kcopyd: add dm_kcopyd_zero to zero an area 2011-10-31 20:18:58 +00:00
dm-linear.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-log-userspace-base.c Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux 2011-11-06 19:44:47 -08:00
dm-log-userspace-transfer.c netlink: kill eff_cap from struct netlink_skb_parms 2011-03-03 13:32:07 -08:00
dm-log-userspace-transfer.h dm log: userspace add luid to distinguish between concurrent log instances 2009-09-04 20:40:34 +01:00
dm-log.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-mpath.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-mpath.h
dm-path-selector.c md: Add module.h to all files using it implicitly 2011-10-31 19:31:18 -04:00
dm-path-selector.h dm mpath: add start_io and nr_bytes to path selectors 2009-06-22 10:12:27 +01:00
dm-queue-length.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-raid1.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-raid.c dm raid: handle failed devices during start up 2012-03-28 18:41:26 +01:00
dm-region-hash.c Fix common misspellings 2011-03-31 11:26:23 -03:00
dm-round-robin.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-service-time.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-snap-persistent.c md: Add in export.h for files using EXPORT_SYMBOL 2011-10-31 19:31:19 -04:00
dm-snap-transient.c md: Add in export.h for files using EXPORT_SYMBOL 2011-10-31 19:31:19 -04:00
dm-snap.c dm snapshot: skip reading origin when overwriting complete chunk 2011-08-02 12:32:04 +01:00
dm-stripe.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-sysfs.c Driver core: Constify struct sysfs_ops in struct kobj_type 2010-03-07 17:04:49 -08:00
dm-table.c dm: reject trailing characters in sccanf input 2012-03-28 18:41:26 +01:00
dm-target.c dm: error return error for discards 2010-08-12 04:14:14 +01:00
dm-thin-metadata.c dm thin: relax hard limit on the maximum size of a metadata device 2012-03-28 18:41:28 +01:00
dm-thin-metadata.h dm thin: relax hard limit on the maximum size of a metadata device 2012-03-28 18:41:28 +01:00
dm-thin.c dm thin: support read only external snapshot origins 2012-03-28 18:41:28 +01:00
dm-uevent.c md: Add in export.h for files using EXPORT_SYMBOL 2011-10-31 19:31:19 -04:00
dm-uevent.h
dm-zero.c dm: zero silently drop discards 2010-08-12 04:14:12 +01:00
dm.c dm: clear bi_end_io on remapping failure 2012-03-28 18:41:25 +01:00
dm.h dm table: add immutable feature 2011-10-31 20:19:04 +00:00
faulty.c md: tidy up rdev_for_each usage. 2012-03-19 12:46:39 +11:00
Kconfig dm raid: no longer experimental 2012-03-28 18:41:24 +01:00
linear.c md: add proper merge_bvec handling to RAID0 and Linear. 2012-03-19 12:46:39 +11:00
linear.h md/linear: typedef removal: linear_conf_t -> struct linear_conf 2011-10-11 16:48:54 +11:00
Makefile dm: add thin provisioning target 2011-10-31 20:21:18 +00:00
md.c md: Add judgement bb->unacked_exist in function md_ack_all_badblocks(). 2012-03-19 12:46:42 +11:00
md.h md/raid10: handle merge_bvec_fn in member devices. 2012-03-19 12:46:39 +11:00
multipath.c md: tidy up rdev_for_each usage. 2012-03-19 12:46:39 +11:00
multipath.h md/multipath: typedef removal: multipath_conf_t -> struct mpconf 2011-10-11 16:48:57 +11:00
raid0.c md: add proper merge_bvec handling to RAID0 and Linear. 2012-03-19 12:46:39 +11:00
raid0.h md: add proper merge_bvec handling to RAID0 and Linear. 2012-03-19 12:46:39 +11:00
raid1.c md/raid1: handle merge_bvec_fn in member devices. 2012-03-19 12:46:39 +11:00
raid1.h md/raid1: Allocate spare to store replacement devices and their bios. 2011-12-23 10:17:56 +11:00
raid5.c md: tidy up rdev_for_each usage. 2012-03-19 12:46:39 +11:00
raid5.h md/raid5: detect and handle replacements during recovery. 2011-12-23 10:17:53 +11:00
raid10.c md/raid10 - support resizing some RAID10 arrays. 2012-03-19 12:46:40 +11:00
raid10.h md/raid10: prepare data structures for handling replacement. 2011-12-23 10:17:54 +11:00