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# -*- mode: YAML -*-
---

headers: |
  #include <bit>
  #include <regex>
  // rbd feature and io operation validation
  #include "include/stringify.h"
  #include "common/strtol.h"
  #include "librbd/Features.h"
  #include "librbd/io/IoOperations.h"
options:
- name: rbd_default_pool
  type: str
  level: advanced
  desc: default pool for storing new images
  default: rbd
  services:
  - rbd
  validator: |
    [](std::string *value, std::string *error_message) {
      std::regex pattern("^[^@/]+$");
      if (!std::regex_match (*value, pattern)) {
        *value = "rbd";
        *error_message = "invalid RBD default pool, resetting to 'rbd'";
      }
      return 0;
    }
- name: rbd_default_data_pool
  type: str
  level: advanced
  desc: default pool for storing data blocks for new images
  services:
  - rbd
  validator: |
    [](std::string *value, std::string *error_message) {
      std::regex pattern("^[^@/]*$");
      if (!std::regex_match (*value, pattern)) {
        *value = "";
        *error_message = "ignoring invalid RBD data pool";
      }
      return 0;
    }
- name: rbd_default_features
  type: str
  level: advanced
  desc: default v2 image features for new images
  long_desc: 'RBD features are only applicable for v2 images. This setting accepts
    either an integer bitmask value or comma-delimited string of RBD feature names.
    This setting is always internally stored as an integer bitmask value. The mapping
    between feature bitmask value and feature name is as follows: +1 -> layering,
    +2 -> striping, +4 -> exclusive-lock, +8 -> object-map, +16 -> fast-diff, +32
    -> deep-flatten, +64 -> journaling, +128 -> data-pool'
  default: layering,exclusive-lock,object-map,fast-diff,deep-flatten
  services:
  - rbd
  flags:
  - runtime
  validator: |
    [](std::string *value, std::string *error_message) {
      std::stringstream ss;
      uint64_t features = librbd::rbd_features_from_string(*value, &ss);
      // Leave this in integer form to avoid breaking Cinder.  Someday
      // we would like to present this in string form instead...
      *value = stringify(features);
      if (ss.str().size()) {
        return -EINVAL;
      }
      return 0;
    }
- name: rbd_op_threads
  type: uint
  level: advanced
  desc: number of threads to utilize for internal processing
  default: 1
  services:
  - rbd
- name: rbd_op_thread_timeout
  type: uint
  level: advanced
  desc: time in seconds for detecting a hung thread
  default: 60
  services:
  - rbd
- name: rbd_disable_zero_copy_writes
  type: bool
  level: advanced
  desc: Disable the use of zero-copy writes to ensure unstable writes from clients
    cannot cause a CRC mismatch
  default: true
  services:
  - rbd
- name: rbd_non_blocking_aio
  type: bool
  level: advanced
  desc: process AIO ops from a dispatch thread to prevent blocking
  default: true
  services:
  - rbd
- name: rbd_cache
  type: bool
  level: advanced
  desc: whether to enable caching (writeback unless rbd_cache_max_dirty is 0)
  fmt_desc: Enable caching for RADOS Block Device (RBD).
  default: true
  services:
  - rbd
- name: rbd_cache_policy
  type: str
  level: advanced
  desc: cache policy for handling writes.
  fmt_desc: Select the caching policy for librbd.
  default: writearound
  services:
  - rbd
  enum_values:
  - writethrough
  - writeback
  - writearound
- name: rbd_cache_writethrough_until_flush
  type: bool
  level: advanced
  desc: whether to make writeback caching writethrough until flush is called, to be
    sure the user of librbd will send flushes so that writeback is safe
  fmt_desc: Start out in ``writethrough`` mode, and switch to ``writeback``
    after the first flush request is received. Enabling is a
    conservative but safe strategy in case VMs running on RBD volumes
    are too old to send flushes, like the ``virtio`` driver in Linux
    kernels older than 2.6.32.
  default: true
  services:
  - rbd
- name: rbd_cache_size
  type: size
  level: advanced
  desc: cache size in bytes
  fmt_desc: The per-volume RBD client cache size in bytes.
  default: 32_M
  policies: write-back and write-through
  services:
  - rbd
- name: rbd_cache_max_dirty
  type: size
  level: advanced
  desc: dirty limit in bytes - set to 0 for write-through caching
  fmt_desc: The ``dirty`` limit in bytes at which the cache triggers write-back.
    If ``0``, uses write-through caching.
  default: 24_M
  constraint: Must be less than ``rbd_cache_size``.
  policies: write-around and write-back
  services:
  - rbd
- name: rbd_cache_target_dirty
  type: size
  level: advanced
  desc: target dirty limit in bytes
  fmt_desc: The ``dirty target`` before the cache begins writing data to the data
    storage. Does not block writes to the cache.
  default: 16_M
  constraint: Must be less than ``rbd_cache_max_dirty``.
  policies: write-back
  services:
  - rbd
- name: rbd_cache_max_dirty_age
  type: float
  level: advanced
  desc: seconds in cache before writeback starts
  fmt_desc: The number of seconds dirty data is in the cache before writeback starts.
  default: 1
  policies: write-back
  services:
  - rbd
- name: rbd_cache_max_dirty_object
  type: uint
  level: advanced
  desc: dirty limit for objects - set to 0 for auto calculate from rbd_cache_size
  default: 0
  services:
  - rbd
- name: rbd_cache_block_writes_upfront
  type: bool
  level: advanced
  desc: whether to block writes to the cache before the aio_write call completes
  default: false
  services:
  - rbd
- name: rbd_parent_cache_enabled
  type: bool
  level: advanced
  desc: whether to enable rbd shared ro cache
  default: false
  services:
  - rbd
- name: rbd_concurrent_management_ops
  type: uint
  level: advanced
  desc: how many operations can be in flight for a management operation like deleting
    or resizing an image
  default: 10
  services:
  - rbd
  min: 1
- name: rbd_balance_snap_reads
  type: bool
  level: advanced
  desc: distribute snap read requests to random OSD
  default: false
  services:
  - rbd
  see_also:
  - rbd_read_from_replica_policy
- name: rbd_localize_snap_reads
  type: bool
  level: advanced
  desc: localize snap read requests to closest OSD
  default: false
  services:
  - rbd
  see_also:
  - rbd_read_from_replica_policy
- name: rbd_balance_parent_reads
  type: bool
  level: advanced
  desc: distribute parent read requests to random OSD
  default: false
  services:
  - rbd
  see_also:
  - rbd_read_from_replica_policy
- name: rbd_localize_parent_reads
  type: bool
  level: advanced
  desc: localize parent requests to closest OSD
  default: false
  services:
  - rbd
  see_also:
  - rbd_read_from_replica_policy
- name: rbd_sparse_read_threshold_bytes
  type: size
  level: advanced
  desc: threshold for issuing a sparse-read
  long_desc: minimum number of sequential bytes to read against an object before issuing
    a sparse-read request to the cluster. 0 implies it must be a full object read
    to issue a sparse-read, 1 implies always use sparse-read, and any value larger
    than the maximum object size will disable sparse-read for all requests
  default: 64_K
  services:
  - rbd
- name: rbd_readahead_trigger_requests
  type: uint
  level: advanced
  desc: number of sequential requests necessary to trigger readahead
  default: 10
  services:
  - rbd
- name: rbd_readahead_max_bytes
  type: size
  level: advanced
  desc: set to 0 to disable readahead
  fmt_desc: Maximum size of a read-ahead request.  If zero, read-ahead is disabled.
  default: 512_K
  services:
  - rbd
- name: rbd_readahead_disable_after_bytes
  type: size
  level: advanced
  desc: how many bytes are read in total before readahead is disabled
  fmt_desc: After this many bytes have been read from an RBD image, read-ahead
    is disabled for that image until it is closed.  This allows the
    guest OS to take over read-ahead once it is booted.  If zero,
    read-ahead stays enabled.
  default: 50_M
  services:
  - rbd
- name: rbd_clone_copy_on_read
  type: bool
  level: advanced
  desc: copy-up parent image blocks to clone upon read request
  default: false
  services:
  - rbd
- name: rbd_blocklist_on_break_lock
  type: bool
  level: advanced
  desc: whether to blocklist clients whose lock was broken
  default: true
  services:
  - rbd
- name: rbd_blocklist_expire_seconds
  type: uint
  level: advanced
  desc: number of seconds to blocklist - set to 0 for OSD default
  default: 0
  services:
  - rbd
- name: rbd_request_timed_out_seconds
  type: uint
  level: advanced
  desc: number of seconds before maintenance request times out
  default: 30
  services:
  - rbd
- name: rbd_skip_partial_discard
  type: bool
  level: advanced
  desc: skip discard (zero) of unaligned extents within an object
  default: true
  services:
  - rbd
- name: rbd_discard_granularity_bytes
  type: uint
  level: advanced
  desc: minimum aligned size of discard operations
  default: 64_K
  services:
  - rbd
  min: 4_K
  max: 32_M
  validator: |
    [](std::string *value, std::string *error_message) {
      uint64_t f = strict_si_cast<uint64_t>(*value, error_message);
      if (!error_message->empty()) {
        return -EINVAL;
      } else if (!std::has_single_bit(f)) {
        *error_message = "value must be a power of two";
        return -EINVAL;
      }
      return 0;
    }
- name: rbd_enable_alloc_hint
  type: bool
  level: advanced
  desc: when writing a object, it will issue a hint to osd backend to indicate the
    expected size object need
  default: true
  services:
  - rbd
- name: rbd_compression_hint
  type: str
  level: basic
  desc: Compression hint to send to the OSDs during writes
  fmt_desc: Hint to send to the OSDs on write operations. If set to
    ``compressible`` and the OSD ``bluestore_compression_mode``
    setting is ``passive``, the OSD will attempt to compress data.
    If set to ``incompressible`` and the OSD compression setting
    is ``aggressive``, the OSD will not attempt to compress data.
  default: none
  services:
  - rbd
  enum_values:
  - none
  - compressible
  - incompressible
  flags:
  - runtime
- name: rbd_read_from_replica_policy
  type: str
  level: basic
  desc: Read replica policy send to the OSDS during reads
  fmt_desc: |
    Policy for determining which OSD will receive read operations.
    If set to ``default``, each PG's primary OSD will always be used
    for read operations. If set to ``balance``, read operations will
    be sent to a randomly selected OSD within the replica set. If set
    to ``localize``, read operations will be sent to the closest OSD
    as determined by the CRUSH map. Unlike ``rbd_balance_snap_reads``
    and ``rbd_localize_snap_reads`` or ``rbd_balance_parent_reads`` and
    ``rbd_localize_parent_reads``, it affects all read operations, not
    just snap or parent. Note: this feature requires the cluster to
    be configured with a minimum compatible OSD release of Octopus.
  default: default
  services:
  - rbd
  enum_values:
  - default
  - balance
  - localize
  flags:
  - runtime
- name: rbd_tracing
  type: bool
  level: advanced
  desc: true if LTTng-UST tracepoints should be enabled
  default: false
  services:
  - rbd
- name: rbd_blkin_trace_all
  type: bool
  level: advanced
  desc: create a blkin trace for all RBD requests
  default: false
  services:
  - rbd
- name: rbd_validate_pool
  type: bool
  level: advanced
  desc: validate empty pools for RBD compatibility
  default: true
  services:
  - rbd
- name: rbd_validate_names
  type: bool
  level: advanced
  desc: validate new image names for RBD compatibility
  default: true
  services:
  - rbd
- name: rbd_invalidate_object_map_on_timeout
  type: bool
  level: dev
  desc: true if object map should be invalidated when load or update timeout
  default: true
  services:
  - rbd
- name: rbd_auto_exclusive_lock_until_manual_request
  type: bool
  level: advanced
  desc: automatically acquire/release exclusive lock until it is explicitly requested
  default: true
  services:
  - rbd
- name: rbd_move_to_trash_on_remove
  type: bool
  level: basic
  desc: automatically move images to the trash when deleted
  default: false
  services:
  - rbd
- name: rbd_move_to_trash_on_remove_expire_seconds
  type: uint
  level: basic
  desc: default number of seconds to protect deleted images in the trash
  default: 0
  services:
  - rbd
- name: rbd_move_parent_to_trash_on_remove
  type: bool
  level: basic
  desc: move parent with clone format v2 children to the trash when deleted
  default: false
  services:
  - rbd
- name: rbd_mirroring_resync_after_disconnect
  type: bool
  level: advanced
  desc: automatically start image resync after mirroring is disconnected due to being
    laggy
  default: false
  services:
  - rbd
- name: rbd_mirroring_delete_delay
  type: uint
  level: advanced
  desc: time-delay in seconds for rbd-mirror delete propagation
  default: 0
  services:
  - rbd
- name: rbd_mirroring_replay_delay
  type: uint
  level: advanced
  desc: time-delay in seconds for rbd-mirror asynchronous replication
  default: 0
  services:
  - rbd
- name: rbd_mirroring_max_mirroring_snapshots
  type: uint
  level: advanced
  desc: mirroring snapshots limit
  default: 5
  services:
  - rbd
  min: 3
- name: rbd_default_format
  type: uint
  level: advanced
  desc: default image format for new images
  default: 2
  services:
  - rbd
- name: rbd_default_order
  type: uint
  level: advanced
  desc: default order (data block object size) for new images
  long_desc: This configures the default object size for new images. The value is used as a
    power of two, meaning ``default_object_size = 2 ^ rbd_default_order``. Configure a value
    between 12 and 25 (inclusive), translating to 4KiB lower and 32MiB upper limit.
  default: 22
  services:
  - rbd
- name: rbd_default_stripe_count
  type: uint
  level: advanced
  desc: default stripe count for new images
  default: 0
  services:
  - rbd
- name: rbd_default_stripe_unit
  type: size
  level: advanced
  desc: default stripe width for new images
  default: 0
  services:
  - rbd
- name: rbd_default_map_options
  type: str
  level: advanced
  desc: default krbd map options
  services:
  - rbd
- name: rbd_default_clone_format
  type: str
  level: advanced
  desc: default internal format for handling clones
  long_desc: This sets the internal format for tracking cloned images. The setting
    of '1' requires attaching to protected snapshots that cannot be removed until
    the clone is removed/flattened. The setting of '2' will allow clones to be attached
    to any snapshot and permits removing in-use parent snapshots but requires Mimic
    or later clients. The default setting of 'auto' will use the v2 format if the
    cluster is configured to require mimic or later clients.
  default: auto
  services:
  - rbd
  enum_values:
  - '1'
  - '2'
  - auto
  flags:
  - runtime
- name: rbd_journal_order
  type: uint
  level: advanced
  desc: default order (object size) for journal data objects
  default: 24
  services:
  - rbd
  min: 12
  max: 26
- name: rbd_journal_splay_width
  type: uint
  level: advanced
  desc: number of active journal objects
  default: 4
  services:
  - rbd
- name: rbd_journal_commit_age
  type: float
  level: advanced
  desc: commit time interval, seconds
  default: 5
  services:
  - rbd
- name: rbd_journal_object_writethrough_until_flush
  type: bool
  level: advanced
  desc: when enabled, the rbd_journal_object_flush* configuration options are ignored
    until the first flush so that batched journal IO is known to be safe for consistency
  default: true
  services:
  - rbd
- name: rbd_journal_object_flush_interval
  type: uint
  level: advanced
  desc: maximum number of pending commits per journal object
  default: 0
  services:
  - rbd
- name: rbd_journal_object_flush_bytes
  type: size
  level: advanced
  desc: maximum number of pending bytes per journal object
  default: 1_M
  services:
  - rbd
- name: rbd_journal_object_flush_age
  type: float
  level: advanced
  desc: maximum age (in seconds) for pending commits
  default: 0
  services:
  - rbd
- name: rbd_journal_object_max_in_flight_appends
  type: uint
  level: advanced
  desc: maximum number of in-flight appends per journal object
  default: 0
  services:
  - rbd
- name: rbd_journal_pool
  type: str
  level: advanced
  desc: pool for journal objects
  services:
  - rbd
- name: rbd_journal_max_payload_bytes
  type: size
  level: advanced
  desc: maximum journal payload size before splitting
  default: 16_K
  services:
  - rbd
- name: rbd_journal_max_concurrent_object_sets
  type: uint
  level: advanced
  desc: maximum number of object sets a journal client can be behind before it is
    automatically unregistered
  default: 0
  services:
  - rbd
- name: rbd_qos_iops_limit
  type: uint
  level: advanced
  desc: the desired limit of IO operations per second
  default: 0
  services:
  - rbd
- name: rbd_qos_bps_limit
  type: uint
  level: advanced
  desc: the desired limit of IO bytes per second
  default: 0
  services:
  - rbd
- name: rbd_qos_read_iops_limit
  type: uint
  level: advanced
  desc: the desired limit of read operations per second
  default: 0
  services:
  - rbd
- name: rbd_qos_write_iops_limit
  type: uint
  level: advanced
  desc: the desired limit of write operations per second
  default: 0
  services:
  - rbd
- name: rbd_qos_read_bps_limit
  type: uint
  level: advanced
  desc: the desired limit of read bytes per second
  default: 0
  services:
  - rbd
- name: rbd_qos_write_bps_limit
  type: uint
  level: advanced
  desc: the desired limit of write bytes per second
  default: 0
  services:
  - rbd
- name: rbd_qos_iops_burst
  type: uint
  level: advanced
  desc: the desired burst limit of IO operations
  default: 0
  services:
  - rbd
- name: rbd_qos_bps_burst
  type: uint
  level: advanced
  desc: the desired burst limit of IO bytes
  default: 0
  services:
  - rbd
- name: rbd_qos_read_iops_burst
  type: uint
  level: advanced
  desc: the desired burst limit of read operations
  default: 0
  services:
  - rbd
- name: rbd_qos_write_iops_burst
  type: uint
  level: advanced
  desc: the desired burst limit of write operations
  default: 0
  services:
  - rbd
- name: rbd_qos_read_bps_burst
  type: uint
  level: advanced
  desc: the desired burst limit of read bytes
  default: 0
  services:
  - rbd
- name: rbd_qos_write_bps_burst
  type: uint
  level: advanced
  desc: the desired burst limit of write bytes
  default: 0
  services:
  - rbd
- name: rbd_qos_iops_burst_seconds
  type: uint
  level: advanced
  desc: the desired burst duration in seconds of IO operations
  default: 1
  services:
  - rbd
  min: 1
- name: rbd_qos_bps_burst_seconds
  type: uint
  level: advanced
  desc: the desired burst duration in seconds of IO bytes
  default: 1
  services:
  - rbd
  min: 1
- name: rbd_qos_read_iops_burst_seconds
  type: uint
  level: advanced
  desc: the desired burst duration in seconds of read operations
  default: 1
  services:
  - rbd
  min: 1
- name: rbd_qos_write_iops_burst_seconds
  type: uint
  level: advanced
  desc: the desired burst duration in seconds of write operations
  default: 1
  services:
  - rbd
  min: 1
- name: rbd_qos_read_bps_burst_seconds
  type: uint
  level: advanced
  desc: the desired burst duration in seconds of read bytes
  default: 1
  services:
  - rbd
  min: 1
- name: rbd_qos_write_bps_burst_seconds
  type: uint
  level: advanced
  desc: the desired burst duration in seconds of write bytes
  default: 1
  services:
  - rbd
  min: 1
- name: rbd_qos_schedule_tick_min
  type: uint
  level: advanced
  desc: minimum schedule tick (in milliseconds) for QoS
  long_desc: This determines the minimum time (in milliseconds) at which I/Os
    can become unblocked if the limit of a throttle is hit. In terms of the
    token bucket algorithm, this is the minimum interval at which tokens are
    added to the bucket.
  default: 50
  services:
  - rbd
  min: 1
- name: rbd_qos_exclude_ops
  type: str
  level: advanced
  desc: optionally exclude ops from QoS
  long_desc: 'Optionally exclude ops from QoS. This setting accepts either an integer
    bitmask value or comma-delimited string of op names. This setting is always internally
    stored as an integer bitmask value. The mapping between op bitmask value and op
    name is as follows: +1 -> read, +2 -> write, +4 -> discard, +8 -> write_same,
    +16 -> compare_and_write'
  services:
  - rbd
  flags:
  - runtime
  validator: |
    [](std::string *value, std::string *error_message) {
        std::ostringstream ss;
        uint64_t exclude_ops = librbd::io::rbd_io_operations_from_string(*value, &ss);
        // Leave this in integer form to avoid breaking Cinder.  Someday
        // we would like to present this in string form instead...
        *value = stringify(exclude_ops);
        if (ss.str().size()) {
          return -EINVAL;
        }
        return 0;
    }
- name: rbd_discard_on_zeroed_write_same
  type: bool
  level: advanced
  desc: discard data on zeroed write same instead of writing zero
  default: true
  services:
  - rbd
- name: rbd_mtime_update_interval
  type: uint
  level: advanced
  desc: RBD Image modify timestamp refresh interval. Set to 0 to disable modify timestamp
    update.
  default: 60
  services:
  - rbd
  min: 0
- name: rbd_atime_update_interval
  type: uint
  level: advanced
  desc: RBD Image access timestamp refresh interval. Set to 0 to disable access timestamp
    update.
  default: 60
  services:
  - rbd
  min: 0
- name: rbd_io_scheduler
  type: str
  level: advanced
  desc: RBD IO scheduler
  default: simple
  services:
  - rbd
  enum_values:
  - none
  - simple
- name: rbd_io_scheduler_simple_max_delay
  type: uint
  level: advanced
  desc: maximum io delay (in milliseconds) for simple io scheduler (if set to 0 dalay
    is calculated based on latency stats)
  default: 0
  services:
  - rbd
  min: 0
- name: rbd_persistent_cache_mode
  type: str
  level: advanced
  desc: enable persistent write back cache for this volume
  default: disabled
  services:
  - rbd
  enum_values:
  - disabled
  - rwl
  - ssd
- name: rbd_persistent_cache_size
  type: uint
  level: advanced
  desc: size of the persistent write back cache for this volume
  default: 1_G
  services:
  - rbd
  min: 1_G
- name: rbd_persistent_cache_path
  type: str
  level: advanced
  desc: location of the persistent write back cache in a DAX-enabled filesystem on
    persistent memory
  default: /tmp
  services:
  - rbd
- name: rbd_quiesce_notification_attempts
  type: uint
  level: dev
  desc: the number of quiesce notification attempts
  default: 10
  services:
  - rbd
  min: 1
- name: rbd_default_snapshot_quiesce_mode
  type: str
  level: advanced
  desc: default snapshot quiesce mode
  default: required
  services:
  - rbd
  enum_values:
  - required
  - ignore-error
  - skip
- name: rbd_plugins
  type: str
  level: advanced
  desc: comma-delimited list of librbd plugins to enable
  services:
  - rbd
- name: rbd_config_pool_override_update_timestamp
  type: uint
  level: dev
  desc: timestamp of last update to pool-level config overrides
  default: 0
  services:
  - rbd