During an ongoing reshape, the MD kernel runtime reads stripes relative
to data_offset and starts storing the reshaped stripes (with new raid
layout and/or new stripesize and/or new number of stripes) relative
to new_data_offset. This is to avoid writing over any data in place
which is non-atomic by nature and thus be recoverable without data loss
in the transition. MD uses the term out-of-place reshaping for it.
There's 2 other areas we don't have report capability for:
- number of data stripes vs. total stripes
(e.g. raid6 with 7 stripes toal has 5 data stripes)
- number of (rotating) parity/syndrome chunks
(e.g. raid6 with 7 stripes toal has 2 parity chunks; one
per stripe for P-Syndrome and another one for Q-Syndrome)
Thus, add the following reportable keys:
- reshape_len (in current units)
- reshape_len_le (in logical extents)
- data_offset (in sectors)
- new_data_offset ( " )
- data_stripes
- parity_chunks
Enhance lvchange-raid.sh, lvconvert-raid-reshape-linear_to_striped.sh,
lvconvert-raid-reshape-striped_to_linear.sh, lvconvert-raid-reshape.sh
and lvconvert-raid-takeover.sh to make use of new keys.
David Teigland [Tue, 28 Feb 2017 22:15:11 +0000 (16:15 -0600)]
commands: SECONDARY flag changes in cmd defs
Add/remove the SECONDARY_SYNTAX flag to cmd defs.
cmd defs with this flag will be listed under the
ADVANCED USAGE man page section, so that the main
USAGE section contains the most common commands
without distraction.
- When multiple cmd defs do the same thing, one variant
can be displayed in the first list.
- Very advanced, unusual or uncommon commands should be
in the second list.
lvconvert: libdm RAID API compatibility versioning
Commit 27384c52cf6a lowered the maximum number of devices
back to 64 for compatibility.
Because more members have been added to the API in
'struct dm_tree_node_raid_params *', we have to version
the public libdm RAID API to not break any existing users.
Changes:
- keep the previous 'struct dm_tree_node_raid_params' and
dm_tree_node_add_raid_target_with_params()/dm_tree_node_add_raid_target()
in order to expose the already released public RAID API
- introduce 'struct dm_tree_node_raid_params_v2' and additional functions
dm_tree_node_add_raid_target_with_params_v2()/dm_tree_node_add_raid_target_v2()
to be used by the new lvm2 lib reshape extentions
With this new API, the bitfields for rebuild/writemostly legs in
'struct dm_tree_node_raid_params_v2' can be raised to 256 bits
again (253 legs maximum supported in MD kernel).
Mind that we can limit the maximum usable number via the
DEFAULT_RAID{1}_MAX_IMAGES definition in defaults.h.
David Teigland [Fri, 24 Feb 2017 22:43:05 +0000 (16:43 -0600)]
commands: fixes for recent raid changes
- Combine the equivalent lvconvert --type raid defs.
(Two cmd defs must be different without relying
on LV type, which are not known at the time the
cmd def is matched.)
- Remove unused optional options from lvconvert --stripes,
and lvconvert --stripesize.
- Use Number for --stripes_long val type.
- Combine the cmd def for raid reshape cleanup into the
existing start_poll cmd def (they were duplicate defs).
Calls into the raid code from a poll opertion will be
added.
lvconvert: limit libdm to maximum of 64 RAID devices
Commit 64a2fad5d6c6 raised the maximum number of RAID devices to 64.
Commit e2354ea344c2 introduced RAID_BITMAP_SIZE as 4 to have
256 bits (4 * 64 bit array members), thus changing the libdm API
unnecessarilly for the time being.
To not change the API, reduce RAID_BITMAP_SIZE to 1.
Remove an unneeded definition of it from libdm-common.h.
If we ever decide to raise past 64, we'll version the API.
Example command to change the origin of a repository clone:
Public:
git remote set-url origin git://sourceware.org/git/lvm2.git
Committers:
git remote set-url origin git+ssh://sourceware.org/git/lvm2.git
David Teigland [Fri, 24 Feb 2017 20:17:58 +0000 (14:17 -0600)]
lvconvert: fix handling args in combining snapshots
Fixes commit 286d39ee3c433, which was correct except
for a reversed strstr. Now uses strchr, and modifies
a copy of the name so the original argv is preserved.
When requesting a regionsize change during conversions, check
for constraints or the command may fail in the kernel n case
the region size is too smalle or too large thus leaving any
new SubLVs behind.
lvconvert: add missed new test scripts for reshaping
Add aforementioned but forgotten new test scripts
lvconvert-raid-reshape-linear_to_striped.sh,
lvconvert-raid-reshape-striped_to_linear.sh and
lvconvert-raid-reshape.sh
Those presume dm-raid target version 1.10.2
provided by a following kernel patch.
lvconvert/lvcreate: raise maximum number of raid images
Because of contraints in renaming shifted rimage/rmeta LV names
the current RaidLV limit is a maximum of 10 SubLV pairs.
With the previous introduction of reshaping infratructure that
constriant got removed.
Kernel supports 253 since dm-raid target 1.9.0, older kernels 64.
Raise the maximum number of RaidLV rimage/rmeta pairs to 64.
If we want to raise past 64, we have to introdce a check for
the kernel supporting it in lvcreate/lvconvert.
lvconvert: add infrastructure for RaidLV reshaping support
In order to support striped raid5/6/10 LV reshaping (change
of LV type, stripesize or number of legs), this patch
introduces the changes to call the reshaping infratructure
from lv_raid_convert().
Changes:
- add reshaping calls from lv_raid_convert()
- add command definitons for reshaping to tools/command-lines.in
- fix raid_rimage_extents()
- add 2 new test scripts lvconvert-raid-reshape-linear_to_striped.sh
and lvconvert-raid-reshape-striped_to_linear.sh to test
the linear <-> striped multi-step conversions
- add lvconvert-raid-reshape.sh reshaping tests
- enhance lvconvert-raid-takeover.sh with new raid10 tests
lvconvert: add infrastructure for RaidLV reshaping support
In order to support striped raid5/6/10 LV reshaping (change
of LV type, stripesize or number of legs), this patch
introduces more local infrastructure to raid_manip.c
used by followup patches.
Change:
- allow raid_rimage_extents() to calculate raid10
- remove an __unused__ attribute
lvconvert: add infrastructure for RaidLV reshaping support
In order to support striped raid5/6/10 LV reshaping (change
of LV type, stripesize or number of legs), this patch
introduces more local infrastructure to raid_manip.c
used by followup patches.
Change:
- add missing raid1 <-> raid5 conversions to support
linear <-> raid5 <-> raid0(_meta)/striped conversions
- rename related new takeover functions to
_takeover_from_raid1_to_raid5 and _takeover_from_raid5_to_raid1,
because a reshape to > 2 legs is only possible with
raid5 layout
lvconvert: add infrastructure for RaidLV reshaping support
In order to support striped raid5/6/10 LV reshaping (change
of LV type, stripesize or number of legs), this patch
introduces more local infrastructure to raid_manip.c
used by followup patches.
Change:
- enhance _clear_meta_lvs() to support raid0 allowing
raid0_meta -> raid10 conversions to succeed by clearing
the raid0 rmeta images or the kernel will fail because
of discovering reordered raid devices
lvconvert: add infrastructure for RaidLV reshaping support
In order to support striped raid5/6/10 LV reshaping (change
of LV type, stripesize or number of legs), this patch
introduces more local infrastructure to raid_manip.c
used by followup patches.
Changes:
- enhance _raid45610_to_raid0_or_striped_wrapper() to support
raid5_n with 2 areas to raid1 conversion to allow for
striped/raid0(_meta)/raid4/5/6 -> raid1/linear conversions;
rename it to _takeover_downconvert_wrapper to discontinue the
illegible function name
- enhance _striped_or_raid0_to_raid45610_wrapper() to support
raid1 with 2 areas to raid5* conversions to allow for
linear/raid1 -> striped/raid0(_meta)/raid4/5/6 conversions;
rename it to _takeover_upconvert_wrapper for the same reason
lvconvert: add infrastructure for RaidLV reshaping support
In order to support striped raid5/6/10 LV reshaping (change
of LV type, stripesize or number of legs), this patch
introduces more local infrastructure to raid_manip.c
used by followup patches.
Changes:
- add missing possible reshape conversions and conversion options
to allow/prohibit changing stripesize or number fo stripes
- enhance setting convenient riad types in reshape conversions
(e.g. raid1 with 2 legs -> radi5_n)
lvconvert: add infrastructure for RaidLV reshaping support
In order to support striped raid5/6/10 LV reshaping (change
of LV type, stripesize or number of legs), this patch
introduces more local infrastructure to raid_manip.c
used by followup patches.
Changes:
- add _raid_reshape() using the pre/post callbacks and
the stripes add/remove reshape functions introduced before
- and _reshape_requested function checking if a reshape
was requested
lvconvert: add infrastructure for RaidLV reshaping support
In order to support striped raid5/6/10 LV reshaping (change
of LV type, stripesize or number of legs), this patch
introduces more local infrastructure to raid_manip.c
used by followup patches.
Changes:
- add vg metadata update functions
- add pre and post activation callback functions for
proper sequencing of sub lv activations during reshaping
- move and enhance _lv_update_reload_fns_reset_eliminate_lvs()
to support pre and post activation callbacks
- add _reset_flags_passed_to_kernel() which resets anyxi
rebuild/reshape flags after they have been passed into the kernel
and sets the SubLV remove after reshape flags on legs to be removed
lvconvert: add infrastructure for RaidLV reshaping support
In order to support striped raid5/6/10 LV reshaping (change
of LV type, stripesize or number of legs), this patch
introduces more local infrastructure to raid_manip.c
used by followup patches.
Changes:
- add function to support disk adding reshapes
- add function to support disk removing reshapes
- add function to support layout (e.g. raid5ls -> raid5_rs)
or stripesize reshaping
lvconvert: add infrastructure for RaidLV reshaping support
In order to support striped raid5/6/10 LV reshaping (change
of LV type, stripesize or number of legs), this patch
introduces more local infrastructure to raid_manip.c
used by followup patches.
Changes:
- add function providing state of a reshaped RaidLV
- add function to adjust the size of a RaidLV was
reshaped to add/remove stripes
lvconvert: add infrastructure for RaidLV reshaping support
In order to support striped raid5/6/10 LV reshaping (change
of LV type, stripesize or number of legs), this patch
introduces more local infrastructure to raid_manip.c
used by followup patches.
Changes:
- add lv_raid_data_copies returning raid type specific number;
needed for raid10 with more than 2 data copies
- remove _shift_and_rename_image_components() constraint
to support more than 10 raid legs
- add function to calculate total rimage length used by out-of-place
reshape space allocation
- add out-of-place reshape space alloc/relocate/free functions
- move _data_rimages_count() used by reshape space alloc/realocate functions
lvconvert: add infrastructure for RaidLV reshaping support
In order to support striped raid5/6/10 LV reshaping (change
of LV type, stripesize or number of legs), this patch
introduces local infrastructure to raid_manip.c
used by followup patches.
Add functions:
- to check reshaping is supported in target attibute
- to return device health string needed to check
the raid device is ready to reshape
lvconvert: add infrastructure for RaidLV reshaping support
In order to support striped raid5/6/10 LV reshaping (change
of LV type, stripesize or number of legs), this patch
introduces infrastructure prerequisites to be used
by raid_manip.c extensions in followup patches.
This base is needed for allocation of out-of-place
reshape space required by the MD raid personalities to
avoid writing over data in-place when reading off the
current RAID layout or number of legs and writing out
the new layout or to a different number of legs
(i.e. restripe)
Changes:
- add members reshape_len to 'struct lv_segment' to store
out-of-place reshape length per component rimage
- add member data_copies to struct lv_segment
to support more than 2 raid10 data copies
- make alloc_lv_segment() aware of both reshape_len and data_copies
- adjust all alloc_lv_segment() callers to the new API
- add functions to retrieve the current data offset (needed for
out-of-place reshaping space allocation) and the devices count
from the kernel
- make libdm deptree code aware of reshape_len
- add LV flags for disk add/remove reshaping
- support import/export of the new 'struct lv_segment' members
- enhance lv_extend/_lv_reduce to cope with reshape_len
- add seg_is_*/segtype_is_* macros related to reshaping
- add target version check for reshaping
- grow rebuilds/writemostly bitmaps to 246 bit to support kernel maximal
- enhance libdm deptree code to support data_offset (out-of-place reshaping)
and delta_disk (legs add/remove reshaping) target arguments
lvchange: reject writemostly/writebehind on raid1 during resync
The MD kernel raid1 personality does no use any writemostly leg as the primary.
In case a previous linear LV holding data gets upconverted to
raid1 it becomes the primary leg of the new raid1 LV and a full
resynchronization is started to update the new legs.
No writemostly and/or writebehind setting may be allowed during
this initial, full synchronization period of this new raid1 LV
(using the lvchange(8) command), because that would change the
primary (i.e the previous linear LV) thus causing data loss.
lvchange has a bug not preventing this scenario.
Fix rejects setting writemostly and/or writebehind on resychronizing raid1 LVs.
Once we have status in the lvm2 metadata about the linear -> raid upconversion,
we may relax this constraint for other types of resynchronization
(e.g. for user requested "lvchange --resync ").
New lvchange-raid1-writemostly.sh test is added to the test suite.
David Teigland [Wed, 22 Feb 2017 22:50:30 +0000 (16:50 -0600)]
man/help: improve the style of units indicator
We use --foo Number[k|Units] to indicate that
the default units of the number is k, but other
units listed below are also accepted.
Capitalize and underline Units so it is consistent
with other variables, and reference it at the end.
Technically, the k should be bold, but this
tends to make the text visually hard to read
because of the excessive highlights scattered
everywhere. So it's left normal text for now
(it's unlikely to confuse anyone.)
David Teigland [Wed, 22 Feb 2017 22:38:54 +0000 (16:38 -0600)]
man: indicate repeatable options
Print ... after a repeatable option in the OPTIONS section.
An alternative would be to just mention in the text description
that the option is repeatable.
Zdenek Kabelac [Wed, 22 Feb 2017 14:16:20 +0000 (15:16 +0100)]
tests: support zero_dev
When the test would need to try to write some large amount of data
we can give it 'zero' segments - for obvious reason such written data
can't be verified but in some test cases it doesn't really matter.
Usage follows 'error_dev' style.
For now test suite is not supporting any combination of
error/delay/zero segments so only 1 type could be used per PV.
Zdenek Kabelac [Wed, 22 Feb 2017 14:12:54 +0000 (15:12 +0100)]
snapshot: improve removal of active origin volume
Previously when lvremove tried to remove 'active' origin,
it had been asking for every 'snapshot' LV separately
and doing individual single snapshot removals first.
To be faster it now deactivates origin before removal
all connected snapshots.
This avoids multiple reloads of dm table for origin volume
which were unnecessary as origin was meant to be removed as well.
David Teigland [Tue, 21 Feb 2017 20:32:54 +0000 (14:32 -0600)]
man/help: use separate common option lists
There are two kinds of common options:
1. options common to all variants of a given command name
2. options common to all lvm commands
Previously, both kinds of common options were listed together
under "Common options". Now the first are printed under
"Common options for command" (when needed), and the second
are printed under "Common options for lvm" (always).
David Teigland [Tue, 21 Feb 2017 17:40:51 +0000 (11:40 -0600)]
commands: adjust default help output
Remove the "usage notes" which should just
live in the man pages.
When there are 3 or more variants of a command,
print all the options produces a lot of output,
so require --longhelp to print all the options
in these cases.
David Teigland [Mon, 20 Feb 2017 17:23:46 +0000 (11:23 -0600)]
lvresize/lvextend: accept type option
The --type option has previously been accepted for
lvresize/lvextend. Using it did not affect the operation
of the command. The value was simply verified as matching
the current seg type of the LV.
David Teigland [Fri, 17 Feb 2017 17:45:13 +0000 (11:45 -0600)]
lvconvert: include swap behavior in generic pool syntax
For this syntax:
lvconvert --thinpool LV1 --poolmetadata LV2
lvconvert --cachepool LV1 --poolmetadata LV2
Restore the metadata swapping behavior in addition to
the pool creation behavior. When LV1 is already a pool,
the metadata LV will be swapped with LV2.
When LV1 is not a pool, it will be converted to a
pool using the specified LV for metadata.
This syntax is no longer advertised because of the
ambiguous behavior. The primary syntaxes for pool
creation and metadata swapping will be the advertised
methods.
git://sourceware.org / lvm2.git / log