Mike Snitzer 2e6023850e dm snapshot: add optional discard support features ... discard_zeroes_cow - a discard issued to the snapshot device that maps to entire chunks to will zero the corresponding exception(s) in the snapshot's exception store. discard_passdown_origin - a discard to the snapshot device is passed down to the snapshot-origin's underlying device. This doesn't cause copy-out to the snapshot exception store because the snapshot-origin target is bypassed. The discard_passdown_origin feature depends on the discard_zeroes_cow feature being enabled. When these 2 features are enabled they allow a temporarily read-only device that has completely exhausted its free space to recover space. To do so dm-snapshot provides temporary buffer to accommodate writes that the temporarily read-only device cannot handle yet. Once the upper layer frees space (e.g. fstrim to XFS) the discards issued to the dm-snapshot target will be issued to underlying read-only device whose free space was exhausted. In addition those discards will also cause zeroes to be written to the snapshot exception store if corresponding exceptions exist. If the underlying origin device provides deduplication for zero blocks then if/when the snapshot is merged backed to the origin those blocks will become unused. Once the origin has gained adequate space, merging the snapshot back to the thinly provisioned device will permit continued use of that device without the temporary space provided by the snapshot. Requested-by: John Dorminy <jdorminy@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>		2019-07-12 09:59:36 -04:00
..
bcache	bcache: only set BCACHE_DEV_WB_RUNNING when cached device attached	2019-06-13 03:09:15 -06:00
persistent-data	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
dm-bio-prison-v1.c
dm-bio-prison-v1.h
dm-bio-prison-v2.c
dm-bio-prison-v2.h
dm-bio-record.h
dm-bufio.c	dm bufio: Simplify stack trace retrieval	2019-04-29 12:37:52 +02:00
dm-builtin.c
dm-cache-background-tracker.c
dm-cache-background-tracker.h
dm-cache-block-types.h
dm-cache-metadata.c	dm cache metadata: Fix loading discard bitset	2019-04-18 16:18:25 -04:00
dm-cache-metadata.h
dm-cache-policy-internal.h
dm-cache-policy-smq.c
dm-cache-policy.c
dm-cache-policy.h
dm-cache-target.c	dm cache: add support for discard passdown to the origin device	2019-03-05 14:53:52 -05:00
dm-core.h	dm: disable DISCARD if the underlying storage no longer supports it	2019-04-04 15:33:59 -04:00
dm-crypt.c	dm crypt: implement eboiv - encrypted byte-offset initialization vector	2019-07-09 14:14:23 -04:00
dm-delay.c	dm delay: fix a crash when invalid device is specified	2019-04-26 11:29:32 -04:00
dm-dust.c	dm dust: Make dm_dust_init and dm_dust_exit static	2019-05-07 16:05:07 -04:00
dm-era-target.c	treewide: Add SPDX license identifier for more missed files	2019-05-21 10:50:45 +02:00
dm-exception-store.c
dm-exception-store.h	- Improve DM snapshot target's scalability by using finer grained	2019-05-16 15:55:48 -07:00
dm-flakey.c	dm flakey: Properly corrupt multi-page bios.	2018-12-18 09:02:27 -05:00
dm-init.c	dm init: remove trailing newline from calls to DMERR() and DMINFO()	2019-06-25 13:43:09 -04:00
dm-integrity.c	dm integrity: use kzalloc() instead of kmalloc() + memset()	2019-07-09 14:14:20 -04:00
dm-io.c
dm-ioctl.c	dm ioctl: fix hang in early create error condition	2019-05-16 09:52:06 -04:00
dm-kcopyd.c	dm kcopyd: Fix bug causing workqueue stalls	2018-12-18 09:02:26 -05:00
dm-linear.c	dm: Check for device sector overflow if CONFIG_LBDAF is not set	2018-12-18 09:02:26 -05:00
dm-log-userspace-base.c
dm-log-userspace-transfer.c
dm-log-userspace-transfer.h
dm-log-writes.c	dm log writes: fix incorrect comment about the logged sequence example	2019-07-09 14:13:33 -04:00
dm-log.c
dm-mpath.c	dm mpath: always free attached_handler_name in parse_path()	2019-04-30 16:51:30 -04:00
dm-mpath.h
dm-path-selector.c
dm-path-selector.h
dm-queue-length.c
dm-raid.c	dm: eliminate 'split_discard_bios' flag from DM target interface	2019-02-20 23:24:55 -05:00
dm-raid1.c	dm: Check for device sector overflow if CONFIG_LBDAF is not set	2018-12-18 09:02:26 -05:00
dm-region-hash.c
dm-round-robin.c
dm-rq.c	dm: update stale comment in end_clone_bio()	2019-07-09 14:14:20 -04:00
dm-rq.h	dm: remove unused _rq_tio_cache and _rq_cache	2019-03-05 14:48:50 -05:00
dm-service-time.c
dm-snap-persistent.c
dm-snap-transient.c
dm-snap.c	dm snapshot: add optional discard support features	2019-07-12 09:59:36 -04:00
dm-stats.c	mm: convert totalram_pages and totalhigh_pages variables to atomic	2018-12-28 12:11:47 -08:00
dm-stats.h
dm-stripe.c
dm-switch.c	dm switch: use struct_size() in kzalloc()	2019-03-05 14:48:51 -05:00
dm-sysfs.c
dm-table.c	dm table: don't copy from a NULL pointer in realloc_argv()	2019-06-25 14:09:13 -04:00
dm-target.c	dm mpath: fix missing call of path selector type->end_io	2019-04-25 15:38:52 -04:00
dm-thin-metadata.c	dm thin metadata: check if in fail_io mode when setting needs_check	2019-07-02 15:50:08 -04:00
dm-thin-metadata.h	dm thin: fix passdown_double_checking_shared_status()	2019-01-15 16:10:41 -05:00
dm-thin.c	dm thin: add sanity checks to thin-pool and external snapshot creation	2019-03-05 14:53:49 -05:00
dm-uevent.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156	2019-05-30 11:26:35 -07:00
dm-uevent.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156	2019-05-30 11:26:35 -07:00
dm-unstripe.c	dm: Check for device sector overflow if CONFIG_LBDAF is not set	2018-12-18 09:02:26 -05:00
dm-verity-fec.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
dm-verity-fec.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
dm-verity-target.c	dm verity: use message limit for data block corruption message	2019-06-25 14:09:14 -04:00
dm-verity.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428	2019-06-05 17:37:16 +02:00
dm-writecache.c	dm writecache: avoid unnecessary lookups in writecache_find_entry()	2019-04-26 11:48:03 -04:00
dm-zero.c
dm-zoned-metadata.c	dm zoned: Fix zone report handling	2019-04-18 16:17:58 -04:00
dm-zoned-reclaim.c
dm-zoned-target.c	dm zoned: Silence a static checker warning	2019-04-18 16:16:01 -04:00
dm-zoned.h
dm.c	libnvdimm fixes v5.2-rc2	2019-05-25 10:11:23 -07:00
dm.h	dax: Arrange for dax_supported check to span multiple devices	2019-05-20 15:02:08 -07:00
Kconfig	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Makefile	dm: add dust target	2019-04-30 16:37:19 -04:00
md-bitmap.c	treewide: Add SPDX license identifier for missed files	2019-05-21 10:50:45 +02:00
md-bitmap.h
md-cluster.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 45	2019-05-24 17:27:12 +02:00
md-cluster.h
md-faulty.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 47	2019-05-24 17:27:13 +02:00
md-linear.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 47	2019-05-24 17:27:13 +02:00
md-linear.h
md-multipath.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 47	2019-05-24 17:27:13 +02:00
md-multipath.h
md.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 47	2019-05-24 17:27:13 +02:00
md.h	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 47	2019-05-24 17:27:13 +02:00
raid1-10.c
raid1.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 47	2019-05-24 17:27:13 +02:00
raid1.h
raid5-cache.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288	2019-06-05 17:36:37 +02:00
raid5-log.h	raid5: set write hint for PPL	2019-03-12 10:15:18 -07:00
raid5-ppl.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 288	2019-06-05 17:36:37 +02:00
raid5.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 47	2019-05-24 17:27:13 +02:00
raid5.h	md: convert to kvmalloc	2019-03-12 10:04:02 -07:00
raid10.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 47	2019-05-24 17:27:13 +02:00
raid10.h
raid0.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 47	2019-05-24 17:27:13 +02:00
raid0.h