IF YOU WOULD LIKE TO GET AN ACCOUNT, please write an
email to Administrator. User accounts are meant only to access repo
and report issues and/or generate pull requests.
This is a purpose-specific Git hosting for
BaseALT
projects. Thank you for your understanding!
Только зарегистрированные пользователи имеют доступ к сервису!
Для получения аккаунта, обратитесь к администратору.
lvm dumpconfig [--ignoreadvanced] [--ignoreunsupported]
--ignoreadvanced causes the advanced configuration options to be left
out on dumpconfig output
--ignoreunsupported causes the options that are not officially supported
to be lef out on dumpconfig output
This shows up in the output as a short commentary:
$ lvm dumpconfig --type default --withcomments metadata/disk_areas
# Configuration option metadata/disk_areas.
# This configuration option is advanced.
# This configuration option is not officially supported.
disk_areas=""
lvm dumpconfig [--withcomments] [--withversions]
The --withcomments causes the comments to appear on output before each
config node (if they were defined in config_settings.h).
The --withversions causes a one line extra comment to appear on output
before each config node with the version information in which the
configuration setting first appeared.
There's a possibility to interconnect the dm_config_node with an
ID, which in our case is used to reference the configuration
definition ID from config_settings.h. So simply interconnecting
struct dm_config_node with struct cfg_def_item.
This patch also adds support for enhanced config node output besides
existing "output line by line". This patch adds a possibility to
register a callback that gets called *before* the config node is
processed line by line (for example to include any headers on output)
and *after* the config node is processed line by line (to include any
footers on output). Also, it adds the config node reference itself
as the callback arg in addition to have a possibility to extract more
information from the config node itself if needed when processing the
output callback (e.g. the key name, the id, or whether this is a
section or a value etc...).
If the config node from lvm.conf/--config tree is recognized and valid,
it's always coupled with the config node definition ID from
config_settings.h:
struct dm_config_node {
int id;
const char *key;
struct dm_config_node *parent, *sib, *child;
struct dm_config_value *v;
}
For example if the dm_config_node *cn holds "devices/dev" configuration,
then the cn->id holds "devices_dev_CFG" ID from config_settings.h, -1 if
not found in config_settings.h and 0 if matching has not yet been done.
To support the enhanced config node output, a new structure has been
defined in libdevmapper to register it:
struct dm_config_node_out_spec {
dm_config_node_out_fn prefix_fn; /* called before processing config node lines */
dm_config_node_out_fn line_fn; /* called for each config node line */
dm_config_node_out_fn suffix_fn; /* called after processing config node lines */
};
Where dm_config_node_out_fn is:
typedef int (*dm_config_node_out_fn)(const struct dm_config_node *cn, const char *line, void *baton);
(so in comparison to existing callbacks for config node output, it has
an extra dm_config_node *cn arg in addition)
This patch also adds these functions to libdevmapper:
- dm_config_write_node_out
- dm_config_write_one_node_out
...which have exactly the same functionality as their counterparts
without the "out" suffix. The "*_out" functions adds the extra hooks
for enhanced config output (prefix_fn and suffix_fn mentioned above).
One can still use the old interface for config node output, this is
just an enhancement for those who'd like to modify the output more
extensively.
lvm dumpconfig [--type {current|default|missing|new}] [--atversion] [--validate]
This patch adds above-mentioned args to lvm dumpconfig and it maps them
to creation and writing out a configuration tree of a specific type
(see also previous commit):
- current maps to CFG_TYPE_CURRENT
- default maps to CFG_TYPE_DEFAULT
- missing maps to CFG_TYPE_MISSING
- new maps to CFG_TYPE_NEW
If --type is not defined, dumpconfig defaults to "--type current"
which is the original behaviour of dumpconfig before all these changes.
The --validate option just validates current configuration tree
(lvm.conf/--config) and it writes a simple status message:
"LVM configuration valid" or "LVM configuration invalid"
Configuration checking is initiated during config load/processing
(_process_config fn) which is part of the command context
creation/refresh.
This patch also defines 5 types of trees that could be created from
the configuration definition (config_settings.h), the cfg_def_tree_t:
- CFG_DEF_TREE_CURRENT that denotes a tree of all the configuration
nodes that are explicitly defined in lvm.conf/--config
- CFG_DEF_TREE_MISSING that denotes a tree of all missing
configuration nodes for which default valus are used since they're
not explicitly used in lvm.conf/--config
- CFG_DEF_TREE_DEFAULT that denotes a tree of all possible
configuration nodes with default values assigned, no matter what
the actual lvm.conf/--config is
- CFG_DEF_TREE_NEW that denotes a tree of all new configuration nodes
that appeared in given version
- CFG_DEF_TREE_COMPLETE that denotes a tree of the whole configuration
tree that is used in LVM2 (a combination of CFG_DEF_TREE_CURRENT +
CFG_DEF_TREE_MISSING). This is not implemented yet, it will be added
later...
The function that creates the definition tree of given type:
struct dm_config_tree *config_def_create_tree(struct config_def_tree_spec *spec);
Where the "spec" specifies the tree type to be created:
struct config_def_tree_spec {
cfg_def_tree_t type; /* tree type */
uint16_t version; /* tree at this LVM2 version */
int ignoreadvanced; /* do not include advanced configs */
int ignoreunsupported; /* do not include unsupported configs */
};
This tree can be passed to already existing functions that write
the tree on output (like we already do with cmd->cft).
There is a new lvm.conf section called "config" with two new options:
- config/checks which enables/disables checking (enabled by default)
- config/abort_on_errors which enables/disables aborts on any type of
mismatch found in the config (disabled by default)
Add support for configuration checking - type checking and recognition
of registered configuration settings that LVM2 understands and also
check the structure of the configuration. Log error on any mismatch
found.
A hash over all allowed configuration paths is created which helps
with matching the exact configuration (lvm.conf/--config tree) with
the configuration item definition from config_settings.h in an
efficient and one-step way.
Two more helper flags are introduced for each configuration definition
item:
- CFG_USED which marks the item as being used (lvm.conf/--config)
This helps with identifying missing configuration options
(and for which defaults were used) when traversing the tree later.
- CFG_VALID which denotes that the item has already been checked and
it was found valid. This improves performance, so if the check
is called once again on the same tree which was not reloaded, we
can just return the state from previous check (with a possibility
to force the check if needed).
The new function that config.h exports and which is going to be used
to perform the configuration checking is:
int config_def_check(struct cmd_context *cmd, int force, int skip, int suppress_messages)
...which is exported internally via config.h.
Export this functionality from libdevmapper just for
convenience and general use when reading boolean values
which could be defined either in a numeric way with 0/1
or by using strings with "true"/"false", "yes"/"no",
"on"/"off", "y"/"n".
For example, the old call and reference:
find_config_tree_str(cmd, "devices/dir", DEFAULT_DEV_DIR)
...now becomes:
find_config_tree_str(cmd, devices_dir_CFG)
So we're referring to the named configuration ID instead
of passing the configuration path and the default value
is taken from central config definition in config_settings.h
automatically.
This patch adds basic structures that encapsulate the config_settings.h
content - it takes each item and puts it in structures:
- cfg_def_type_t to define config item type
- cfg_def_value_t to define config item (default) value
- flags used to define the nature and use of the config item:
- CFG_NAME_VARIABLE for items with variable names (e.g. tags)
- CFG_ALLOW_EMPTY for items where empty value is allowed
- CFG_ADVANCED for items which are considered as "advanced settings"
- CFG_UNSUPPORTED for items which are not officially supported
(config options mostly for internal use and testing/debugging)
- cfg_def_item_t to encapsulate the whole definition of the config
definition itself
Each config item is referenced by named ID, e.g. "devices_dir_CFG"
instead of directly typing the path "devices/dir" as it was before.
This patch also adds cfg_def_get_path helper function to get the
config setting path up to the root for given config ID
(it returns the path in form of "abc/def/.../xyz" where the "abc"
is the topmost element).
This file centrally defines all recognized LVM2 configuration
sections and settings. Each item here has its parent, set of
allowed types, default value, brief comment, version the setting
first appeared in and flags that further define the nature of
the configuration setting and its use.
When a section was empty in a configuration tree (no children - this is
allowed) and we were looking for a config node inside that section, the
_find_config_node function incorrectly returned the section itself if
the node inside that section was not found.
For example the configuration below:
The config:
abc {
}
And a function call to get the "def" node inside "abc" section:
_find_config_node(..., "abc/def")
...returned the "abc" node instead of NULL ("def" not found).
This in turn caused segfaults in the code using lookups in such
a configuration tree as we (correctly) expected that the node
returned was always the one we were looking for or NULL if not
found. But if incorrect node was returned instead, we processed
that as if this was the node we were looking for and so we
processed its value as well. But sections don't have values => segfault.
Just to prevent accidental and improper use when reading the layout
from disk because of the already existing disk_areas_xl[0] lists
that are variable in size. We can read pv_header_extension only
after we know exactly where the lists end...
There are new reporting fields for Embedding Area: ea_start and ea_size.
An example of 1m Embedding Area and relevant reporting fields:
raw/~ # pvs -o pv_name,pe_start,ea_start,ea_size
PV 1st PE EA start EA size
/dev/sda 2.00m 1.00m 1.00m
To create an Embedding Area during PV creation (pvcreate or as part of
the vgconvert operation), we need to define the Embedding Area size.
The Embedding Area start will be calculated automatically by the tools.
This patch adds --embeddingareasize argument to pvcreate and vgconvert.
The PV header extension information (PV header extension version, flags
and list of Embedding Area locations) is stored just beyond the PV header base.
When calculating the Embedding Area start value (ea_start), the same logic is
used as when calculating the pe_start value for Data Area - the value must
follow exactly the same alignment restrictions for its start value
(the alignment detected automatically or provided via command line using
the --dataalignment and --dataalignmentoffset arguments).
The Embedding Area is placed at the very start of the PV, starting at
ea_start. The Data Area starting at pe_start is placed next. The pe_start is
still properly aligned. Due to the pe_start alignment, it's possible that the
resulting Embedding Area size (ea_size) ends up bigger in size than requested
(but never less than requested).
New tools with PV header extension support will read the extension
if it exists and it's not an error if it does not exist (so old PVs
will still work seamlessly with new tools).
Old tools without PV header extension support will just ignore any
extension.
As for the Embedding Area location information (its start and size),
there are actually two places where this is stored:
- PV header extension
- VG metadata
The VG metadata contains a copy of what's written in the PV header
extension about the Embedding Area location (NULL value is not copied):
physical_volumes {
pv0 {
id = "AkSSRf-difg-fCCZ-NjAN-qP49-1zzg-S0Fd4T"
device = "/dev/sda" # Hint only
status = ["ALLOCATABLE"]
flags = []
dev_size = 262144 # 128 Megabytes
pe_start = 67584
pe_count = 23 # 92 Megabytes
ea_start = 2048
ea_size = 65536 # 32 Megabytes
}
}
The new metadata fields are "ea_start" and "ea_size".
This is mostly useful when restoring the PV by using existing
metadata backups (e.g. pvcreate --restorefile ...).
New tools does not require these two fields to exist in VG metadata,
they're not compulsory. Therefore, reading old VG metadata which doesn't
contain any Embedding Area information will not end up with any kind
of error but only a debug message that the ea_start and ea_size values
were not found.
Old tools just ignore these extra fields in VG metadata.
PV header extension comes just beyond the existing PV header base:
PV header base (existing):
- uuid
- device size
- null-terminated list of Data Areas
- null-terminater list of MetaData Areas
PV header extension:
- extension version
- flags
- null-terminated list of Embedding Areas
This patch also adds "eas" (Embedding Areas) list to lvmcache (lvmcache_info)
and it also adds support for common operations on the list (just like for
already existing "das" - Data Areas list):
- lvmcache_add_ea
- lvmcache_update_eas
- lvmcache_foreach_ea
- lvmcache_del_eas
Also, add ea_start and ea_size to struct physical_volume for processing
PV Embedding Area location throughout the code (currently only one
Embedding Area is supported, though the definition on disk allows for
more if needed in the future...).
Also, define FMT_EAS format flag to mark that the format actually
supports Embedding Areas (currently format-text only).
Extract restorable PV creation parameters from struct pvcreate_params into
a separate struct pvcreate_restorable_params for clarity and also for better
maintainability when adding any new items later.
Add basic support for converting LV into an external origin volume.
Syntax:
lvconvert --thinpool vg/pool --originname renamed_origin -T origin
It will convert volume 'origin' into a thin volume, which will
use 'renamed_origin' as an external read-only origin.
All read/write into origin will go via 'pool'.
renamed_origin volume is read-only volume, that could be activated
only in read-only mode, and cannot be modified.
Use the field 'origin' for reporting external origin lv name.
For thin volumes with external origin, report the size of
external origin size via:
lvs -o+origin_size
Do not allow conversion of external origin into writeable LV,
and prohibit changing the external origin size.
If the snapshot origin is also external origin, merge is prohibited.
Reorder activation code to look similar for preload tree and
activation tree.
Its also give much better suppport for device stacking,
since now we also support activation of snapshot which might
be then used for other devices.
A new function (dm_tree_node_force_identical_table_reload) was added to
avoid the suppression of identical table reloads. This allows RAID LVs
to reload the on-disk superblock information that contains which devices
have failed and the bitmaps. If the failed device has returned, this has
the effect of restoring the device and initiating recovery. Without this
patch, the user had to completely deactivate their RAID LV and re-activate
it in order to restore the failed device. Now they simply need to
suspend and resume (which is done by 'lvchange --refresh').
The identical table suppression is only avoided if the LV is not PARTAIL
(i.e. all of it's devices can be seen and read by LVM) and the kernel
status of the array contains failed devices. In other words, the function
will only be called in the case where we may have success in restoring
a failed device in the array.
When there are missing PVs in a volume group, most operations that alter
the LVM metadata are disallowed. It turns out that 'vgimport' is one of
those disallowed operations. This is bad because it creates a circular
dependency. 'vgimport' will complain that the VG is inconsistent and that
'vgreduce --removemissing' must be run. However, 'vgreduce' cannot be run
because it has not been imported. Therefore, 'vgimport' must be one of
the operations allowed to change the metadata when PVs are missing. The
'--force' option is the way to make 'vgimport' happen in spite of the
missing PVs.
If zero metadata copies are used, there's no further recalculation of
PV alignment that happens when adding metadata areas to the PV and
which actually calculates the alignment correctly as a matter of fact.
So fix this for "PV without MDA" case as well.
Before this patch:
[1] raw/~ # pvcreate --dataalignment 8m --dataalignmentoffset 4m
--metadatacopies 1 /dev/sda
Physical volume "/dev/sda" successfully created
[1] raw/~ # pvs -o pv_name,pe_start
PV 1st PE
/dev/sda 12.00m
[1] raw/~ # pvcreate --dataalignment 8m --dataalignmentoffset 4m
--metadatacopies 0 /dev/sda
Physical volume "/dev/sda" successfully created
[1] raw/~ # pvs -o pv_name,pe_start
PV 1st PE
/dev/sda 8.00m
After this patch:
[1] raw/~ # pvcreate --dataalignment 8m --dataalignmentoffset 4m
--metadatacopies 1 /dev/sda
Physical volume "/dev/sda" successfully created
[1] raw/~ # pvs -o pv_name,pe_start
PV 1st PE
/dev/sda 12.00m
[1] raw/~ # pvcreate --dataalignment 8m --dataalignmentoffset 4m
--metadatacopies 0 /dev/sda
Physical volume "/dev/sda" successfully created
[1] raw/~ # pvs -o pv_name,pe_start
PV 1st PE
/dev/sda 12.00m
Also, remove a superfluous condition "pv->pe_start < pv->pe_align" in:
if (pe_start == PV_PE_START_CALC && pv->pe_start < pv->pe_align)
pv->pe_start = pv->pe_align ...
This part of the condition is not reachable as with the PV_PE_START_CALC,
we always have pv->pe_start set to 0 from the PV struct initialisation
(...the pv->pe_start value is just being calculated).
If '--mirrors/-m' and '--stripes/-i' are used together when creating
a logical volume, mirrors-over-stripes is currently chosen. The user
can override this by using the '--type raid10' option on creation.
However, we want a place where we can set the default behavior to
'raid10' explicitly - similar to the "mirror" and "raid1" tunable,
mirror_segtype_default.
A follow-on patch should use this new setting to change the default
from "mirror" to "raid10", as this is the preferred segment type.
When a device fails, we may wish to replace those segments with an
error segment. (Like when a 'vgreduce --removemissing' removes a
failed device that happens to be a RAID image/meta.) We are then left
with images that we will eventually want to remove or replace.
This patch allows us to pull out these virtual "error" sub-LVs. This
allows a user to 'lvconvert -m -1 vg/lv' to extract the bad sub-LVs.
Sub-LVs with error segments are considered for extraction before other
possible devices so that good devices are not accidentally removed.
This patch also adds the ability to replace RAID images that contain error
segments. The user will still be unable to run 'lvconvert --replace'
because there is no way to address the 'error' segment (i.e. no PV
that it is associated with). However, 'lvconvert --repair' can be
used to replace the image's error segment with a new PV. This is also
the most appropriate way to do it, since the LV will continue to be
reported as 'partial'.
Currently it is impossible to remove a failed PV which has a RAID LV
on it. This patch fixes the issue by replacing the failed PV with an
'error' segment within the affected sub-LVs. Once there is no longer
a RAID LV using the PV, it can be removed.
Most often, it is better to replace a failed RAID device with a spare.
(You can use 'lvconvert --repair <vg>/<LV>' to accomplish that.)
However, if there are no spares in the volume group and none will be
added, it is useful to be able to removed the failed device.
Following patches address the ability to perform 'lvconvert' operations
on RAID LVs that contain sub-LVs composed of 'error' segments.
We have been using 'mirror_region_size' in lvm.conf as the default region
size for RAID logical volumes as well as mirror logical volumes. Since,
"raid" is more inclusive and representative than "mirror", I have changed
the name of this setting. We must still check for the old setting and warn
the user if we are overriding it with the new setting if both happen to be
present.
