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linux/include/linux/drbd_genl.h
Philipp Reisner 5d0b17f1a2 drbd: New net configuration option socket-check-timeout 
In setups involving a DRBD-proxy and connections that experience a lot of
buffer-bloat it might be necessary to set ping-timeout to an
unusual high value. By default DRBD uses the same value to wait if a newly
established TCP-connection is stable. Since the DRBD-proxy is usually located
in the same data center such a long wait time may hinder DRBD's connect process.

In such setups socket-check-timeout should be set to
at least to the round trip time between DRBD and DRBD-proxy. I.e. in most
cases to 1.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2014-07-10 18:35:01 +02:00

385 lines
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/*
* General overview:
* full generic netlink message:
* |nlmsghdr|genlmsghdr|<payload>
*
* payload:
* |optional fixed size family header|<sequence of netlink attributes>
*
* sequence of netlink attributes:
* I chose to have all "top level" attributes NLA_NESTED,
* corresponding to some real struct.
* So we have a sequence of |tla, len|<nested nla sequence>
*
* nested nla sequence:
* may be empty, or contain a sequence of netlink attributes
* representing the struct fields.
*
* The tag number of any field (regardless of containing struct)
* will be available as T_ ## field_name,
* so you cannot have the same field name in two differnt structs.
*
* The tag numbers themselves are per struct, though,
* so should always begin at 1 (not 0, that is the special "NLA_UNSPEC" type,
* which we won't use here).
* The tag numbers are used as index in the respective nla_policy array.
*
* GENL_struct(tag_name, tag_number, struct name, struct fields) - struct and policy
* genl_magic_struct.h
* generates the struct declaration,
* generates an entry in the tla enum,
* genl_magic_func.h
* generates an entry in the static tla policy
* with .type = NLA_NESTED
* generates the static <struct_name>_nl_policy definition,
* and static conversion functions
*
* genl_magic_func.h
*
* GENL_mc_group(group)
* genl_magic_struct.h
* does nothing
* genl_magic_func.h
* defines and registers the mcast group,
* and provides a send helper
*
* GENL_notification(op_name, op_num, mcast_group, tla list)
* These are notifications to userspace.
*
* genl_magic_struct.h
* generates an entry in the genl_ops enum,
* genl_magic_func.h
* does nothing
*
* mcast group: the name of the mcast group this notification should be
* expected on
* tla list: the list of expected top level attributes,
* for documentation and sanity checking.
*
* GENL_op(op_name, op_num, flags and handler, tla list) - "genl operations"
* These are requests from userspace.
*
* _op and _notification share the same "number space",
* op_nr will be assigned to "genlmsghdr->cmd"
*
* genl_magic_struct.h
* generates an entry in the genl_ops enum,
* genl_magic_func.h
* generates an entry in the static genl_ops array,
* and static register/unregister functions to
* genl_register_family_with_ops().
*
* flags and handler:
* GENL_op_init( .doit = x, .dumpit = y, .flags = something)
* GENL_doit(x) => .dumpit = NULL, .flags = GENL_ADMIN_PERM
* tla list: the list of expected top level attributes,
* for documentation and sanity checking.
*/
/*
* STRUCTS
*/
/* this is sent kernel -> userland on various error conditions, and contains
* informational textual info, which is supposedly human readable.
* The computer relevant return code is in the drbd_genlmsghdr.
*/
GENL_struct(DRBD_NLA_CFG_REPLY, 1, drbd_cfg_reply,
/* "arbitrary" size strings, nla_policy.len = 0 */
__str_field(1, DRBD_GENLA_F_MANDATORY, info_text, 0)
)
/* Configuration requests typically need a context to operate on.
* Possible keys are device minor (fits in the drbd_genlmsghdr),
* the replication link (aka connection) name,
* and/or the replication group (aka resource) name,
* and the volume id within the resource. */
GENL_struct(DRBD_NLA_CFG_CONTEXT, 2, drbd_cfg_context,
__u32_field(1, DRBD_GENLA_F_MANDATORY, ctx_volume)
__str_field(2, DRBD_GENLA_F_MANDATORY, ctx_resource_name, 128)
__bin_field(3, DRBD_GENLA_F_MANDATORY, ctx_my_addr, 128)
__bin_field(4, DRBD_GENLA_F_MANDATORY, ctx_peer_addr, 128)
)
GENL_struct(DRBD_NLA_DISK_CONF, 3, disk_conf,
__str_field(1, DRBD_F_REQUIRED | DRBD_F_INVARIANT, backing_dev, 128)
__str_field(2, DRBD_F_REQUIRED | DRBD_F_INVARIANT, meta_dev, 128)
__s32_field(3, DRBD_F_REQUIRED | DRBD_F_INVARIANT, meta_dev_idx)
/* use the resize command to try and change the disk_size */
__u64_field(4, DRBD_GENLA_F_MANDATORY | DRBD_F_INVARIANT, disk_size)
/* we could change the max_bio_bvecs,
* but it won't propagate through the stack */
__u32_field(5, DRBD_GENLA_F_MANDATORY | DRBD_F_INVARIANT, max_bio_bvecs)
__u32_field_def(6, DRBD_GENLA_F_MANDATORY, on_io_error, DRBD_ON_IO_ERROR_DEF)
__u32_field_def(7, DRBD_GENLA_F_MANDATORY, fencing, DRBD_FENCING_DEF)
__u32_field_def(8, DRBD_GENLA_F_MANDATORY, resync_rate, DRBD_RESYNC_RATE_DEF)
__s32_field_def(9, DRBD_GENLA_F_MANDATORY, resync_after, DRBD_MINOR_NUMBER_DEF)
__u32_field_def(10, DRBD_GENLA_F_MANDATORY, al_extents, DRBD_AL_EXTENTS_DEF)
__u32_field_def(11, DRBD_GENLA_F_MANDATORY, c_plan_ahead, DRBD_C_PLAN_AHEAD_DEF)
__u32_field_def(12, DRBD_GENLA_F_MANDATORY, c_delay_target, DRBD_C_DELAY_TARGET_DEF)
__u32_field_def(13, DRBD_GENLA_F_MANDATORY, c_fill_target, DRBD_C_FILL_TARGET_DEF)
__u32_field_def(14, DRBD_GENLA_F_MANDATORY, c_max_rate, DRBD_C_MAX_RATE_DEF)
__u32_field_def(15, DRBD_GENLA_F_MANDATORY, c_min_rate, DRBD_C_MIN_RATE_DEF)
__flg_field_def(16, DRBD_GENLA_F_MANDATORY, disk_barrier, DRBD_DISK_BARRIER_DEF)
__flg_field_def(17, DRBD_GENLA_F_MANDATORY, disk_flushes, DRBD_DISK_FLUSHES_DEF)
__flg_field_def(18, DRBD_GENLA_F_MANDATORY, disk_drain, DRBD_DISK_DRAIN_DEF)
__flg_field_def(19, DRBD_GENLA_F_MANDATORY, md_flushes, DRBD_MD_FLUSHES_DEF)
__u32_field_def(20, DRBD_GENLA_F_MANDATORY, disk_timeout, DRBD_DISK_TIMEOUT_DEF)
__u32_field_def(21, 0 /* OPTIONAL */, read_balancing, DRBD_READ_BALANCING_DEF)
/* 9: __u32_field_def(22, DRBD_GENLA_F_MANDATORY, unplug_watermark, DRBD_UNPLUG_WATERMARK_DEF) */
__flg_field_def(23, 0 /* OPTIONAL */, al_updates, DRBD_AL_UPDATES_DEF)
)
GENL_struct(DRBD_NLA_RESOURCE_OPTS, 4, res_opts,
__str_field_def(1, DRBD_GENLA_F_MANDATORY, cpu_mask, DRBD_CPU_MASK_SIZE)
__u32_field_def(2, DRBD_GENLA_F_MANDATORY, on_no_data, DRBD_ON_NO_DATA_DEF)
)
GENL_struct(DRBD_NLA_NET_CONF, 5, net_conf,
__str_field_def(1, DRBD_GENLA_F_MANDATORY | DRBD_F_SENSITIVE,
shared_secret, SHARED_SECRET_MAX)
__str_field_def(2, DRBD_GENLA_F_MANDATORY, cram_hmac_alg, SHARED_SECRET_MAX)
__str_field_def(3, DRBD_GENLA_F_MANDATORY, integrity_alg, SHARED_SECRET_MAX)
__str_field_def(4, DRBD_GENLA_F_MANDATORY, verify_alg, SHARED_SECRET_MAX)
__str_field_def(5, DRBD_GENLA_F_MANDATORY, csums_alg, SHARED_SECRET_MAX)
__u32_field_def(6, DRBD_GENLA_F_MANDATORY, wire_protocol, DRBD_PROTOCOL_DEF)
__u32_field_def(7, DRBD_GENLA_F_MANDATORY, connect_int, DRBD_CONNECT_INT_DEF)
__u32_field_def(8, DRBD_GENLA_F_MANDATORY, timeout, DRBD_TIMEOUT_DEF)
__u32_field_def(9, DRBD_GENLA_F_MANDATORY, ping_int, DRBD_PING_INT_DEF)
__u32_field_def(10, DRBD_GENLA_F_MANDATORY, ping_timeo, DRBD_PING_TIMEO_DEF)
__u32_field_def(11, DRBD_GENLA_F_MANDATORY, sndbuf_size, DRBD_SNDBUF_SIZE_DEF)
__u32_field_def(12, DRBD_GENLA_F_MANDATORY, rcvbuf_size, DRBD_RCVBUF_SIZE_DEF)
__u32_field_def(13, DRBD_GENLA_F_MANDATORY, ko_count, DRBD_KO_COUNT_DEF)
__u32_field_def(14, DRBD_GENLA_F_MANDATORY, max_buffers, DRBD_MAX_BUFFERS_DEF)
__u32_field_def(15, DRBD_GENLA_F_MANDATORY, max_epoch_size, DRBD_MAX_EPOCH_SIZE_DEF)
__u32_field_def(16, DRBD_GENLA_F_MANDATORY, unplug_watermark, DRBD_UNPLUG_WATERMARK_DEF)
__u32_field_def(17, DRBD_GENLA_F_MANDATORY, after_sb_0p, DRBD_AFTER_SB_0P_DEF)
__u32_field_def(18, DRBD_GENLA_F_MANDATORY, after_sb_1p, DRBD_AFTER_SB_1P_DEF)
__u32_field_def(19, DRBD_GENLA_F_MANDATORY, after_sb_2p, DRBD_AFTER_SB_2P_DEF)
__u32_field_def(20, DRBD_GENLA_F_MANDATORY, rr_conflict, DRBD_RR_CONFLICT_DEF)
__u32_field_def(21, DRBD_GENLA_F_MANDATORY, on_congestion, DRBD_ON_CONGESTION_DEF)
__u32_field_def(22, DRBD_GENLA_F_MANDATORY, cong_fill, DRBD_CONG_FILL_DEF)
__u32_field_def(23, DRBD_GENLA_F_MANDATORY, cong_extents, DRBD_CONG_EXTENTS_DEF)
__flg_field_def(24, DRBD_GENLA_F_MANDATORY, two_primaries, DRBD_ALLOW_TWO_PRIMARIES_DEF)
__flg_field(25, DRBD_GENLA_F_MANDATORY | DRBD_F_INVARIANT, discard_my_data)
__flg_field_def(26, DRBD_GENLA_F_MANDATORY, tcp_cork, DRBD_TCP_CORK_DEF)
__flg_field_def(27, DRBD_GENLA_F_MANDATORY, always_asbp, DRBD_ALWAYS_ASBP_DEF)
__flg_field(28, DRBD_GENLA_F_MANDATORY | DRBD_F_INVARIANT, tentative)
__flg_field_def(29, DRBD_GENLA_F_MANDATORY, use_rle, DRBD_USE_RLE_DEF)
/* 9: __u32_field_def(30, DRBD_GENLA_F_MANDATORY, fencing_policy, DRBD_FENCING_DEF) */
/* 9: __str_field_def(31, DRBD_GENLA_F_MANDATORY, name, SHARED_SECRET_MAX) */
/* 9: __u32_field(32, DRBD_F_REQUIRED | DRBD_F_INVARIANT, peer_node_id) */
__flg_field_def(33, 0 /* OPTIONAL */, csums_after_crash_only, DRBD_CSUMS_AFTER_CRASH_ONLY_DEF)
__u32_field_def(34, 0 /* OPTIONAL */, sock_check_timeo, DRBD_SOCKET_CHECK_TIMEO_DEF)
)
GENL_struct(DRBD_NLA_SET_ROLE_PARMS, 6, set_role_parms,
__flg_field(1, DRBD_GENLA_F_MANDATORY, assume_uptodate)
)
GENL_struct(DRBD_NLA_RESIZE_PARMS, 7, resize_parms,
__u64_field(1, DRBD_GENLA_F_MANDATORY, resize_size)
__flg_field(2, DRBD_GENLA_F_MANDATORY, resize_force)
__flg_field(3, DRBD_GENLA_F_MANDATORY, no_resync)
__u32_field_def(4, 0 /* OPTIONAL */, al_stripes, DRBD_AL_STRIPES_DEF)
__u32_field_def(5, 0 /* OPTIONAL */, al_stripe_size, DRBD_AL_STRIPE_SIZE_DEF)
)
GENL_struct(DRBD_NLA_STATE_INFO, 8, state_info,
/* the reason of the broadcast,
* if this is an event triggered broadcast. */
__u32_field(1, DRBD_GENLA_F_MANDATORY, sib_reason)
__u32_field(2, DRBD_F_REQUIRED, current_state)
__u64_field(3, DRBD_GENLA_F_MANDATORY, capacity)
__u64_field(4, DRBD_GENLA_F_MANDATORY, ed_uuid)
/* These are for broadcast from after state change work.
* prev_state and new_state are from the moment the state change took
* place, new_state is not neccessarily the same as current_state,
* there may have been more state changes since. Which will be
* broadcasted soon, in their respective after state change work. */
__u32_field(5, DRBD_GENLA_F_MANDATORY, prev_state)
__u32_field(6, DRBD_GENLA_F_MANDATORY, new_state)
/* if we have a local disk: */
__bin_field(7, DRBD_GENLA_F_MANDATORY, uuids, (UI_SIZE*sizeof(__u64)))
__u32_field(8, DRBD_GENLA_F_MANDATORY, disk_flags)
__u64_field(9, DRBD_GENLA_F_MANDATORY, bits_total)
__u64_field(10, DRBD_GENLA_F_MANDATORY, bits_oos)
/* and in case resync or online verify is active */
__u64_field(11, DRBD_GENLA_F_MANDATORY, bits_rs_total)
__u64_field(12, DRBD_GENLA_F_MANDATORY, bits_rs_failed)
/* for pre and post notifications of helper execution */
__str_field(13, DRBD_GENLA_F_MANDATORY, helper, 32)
__u32_field(14, DRBD_GENLA_F_MANDATORY, helper_exit_code)
__u64_field(15, 0, send_cnt)
__u64_field(16, 0, recv_cnt)
__u64_field(17, 0, read_cnt)
__u64_field(18, 0, writ_cnt)
__u64_field(19, 0, al_writ_cnt)
__u64_field(20, 0, bm_writ_cnt)
__u32_field(21, 0, ap_bio_cnt)
__u32_field(22, 0, ap_pending_cnt)
__u32_field(23, 0, rs_pending_cnt)
)
GENL_struct(DRBD_NLA_START_OV_PARMS, 9, start_ov_parms,
__u64_field(1, DRBD_GENLA_F_MANDATORY, ov_start_sector)
__u64_field(2, DRBD_GENLA_F_MANDATORY, ov_stop_sector)
)
GENL_struct(DRBD_NLA_NEW_C_UUID_PARMS, 10, new_c_uuid_parms,
__flg_field(1, DRBD_GENLA_F_MANDATORY, clear_bm)
)
GENL_struct(DRBD_NLA_TIMEOUT_PARMS, 11, timeout_parms,
__u32_field(1, DRBD_F_REQUIRED, timeout_type)
)
GENL_struct(DRBD_NLA_DISCONNECT_PARMS, 12, disconnect_parms,
__flg_field(1, DRBD_GENLA_F_MANDATORY, force_disconnect)
)
GENL_struct(DRBD_NLA_DETACH_PARMS, 13, detach_parms,
__flg_field(1, DRBD_GENLA_F_MANDATORY, force_detach)
)
/*
* Notifications and commands (genlmsghdr->cmd)
*/
GENL_mc_group(events)
/* kernel -> userspace announcement of changes */
GENL_notification(
DRBD_EVENT, 1, events,
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED)
GENL_tla_expected(DRBD_NLA_STATE_INFO, DRBD_F_REQUIRED)
GENL_tla_expected(DRBD_NLA_NET_CONF, DRBD_GENLA_F_MANDATORY)
GENL_tla_expected(DRBD_NLA_DISK_CONF, DRBD_GENLA_F_MANDATORY)
GENL_tla_expected(DRBD_NLA_SYNCER_CONF, DRBD_GENLA_F_MANDATORY)
)
/* query kernel for specific or all info */
GENL_op(
DRBD_ADM_GET_STATUS, 2,
GENL_op_init(
.doit = drbd_adm_get_status,
.dumpit = drbd_adm_get_status_all,
/* anyone may ask for the status,
* it is broadcasted anyways */
),
/* To select the object .doit.
* Or a subset of objects in .dumpit. */
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_GENLA_F_MANDATORY)
)
/* add DRBD minor devices as volumes to resources */
GENL_op(DRBD_ADM_NEW_MINOR, 5, GENL_doit(drbd_adm_new_minor),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED))
GENL_op(DRBD_ADM_DEL_MINOR, 6, GENL_doit(drbd_adm_del_minor),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED))
/* add or delete resources */
GENL_op(DRBD_ADM_NEW_RESOURCE, 7, GENL_doit(drbd_adm_new_resource),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED))
GENL_op(DRBD_ADM_DEL_RESOURCE, 8, GENL_doit(drbd_adm_del_resource),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED))
GENL_op(DRBD_ADM_RESOURCE_OPTS, 9,
GENL_doit(drbd_adm_resource_opts),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED)
GENL_tla_expected(DRBD_NLA_RESOURCE_OPTS, DRBD_GENLA_F_MANDATORY)
)
GENL_op(
DRBD_ADM_CONNECT, 10,
GENL_doit(drbd_adm_connect),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED)
GENL_tla_expected(DRBD_NLA_NET_CONF, DRBD_F_REQUIRED)
)
GENL_op(
DRBD_ADM_CHG_NET_OPTS, 29,
GENL_doit(drbd_adm_net_opts),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED)
GENL_tla_expected(DRBD_NLA_NET_CONF, DRBD_F_REQUIRED)
)
GENL_op(DRBD_ADM_DISCONNECT, 11, GENL_doit(drbd_adm_disconnect),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED))
GENL_op(DRBD_ADM_ATTACH, 12,
GENL_doit(drbd_adm_attach),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED)
GENL_tla_expected(DRBD_NLA_DISK_CONF, DRBD_F_REQUIRED)
)
GENL_op(DRBD_ADM_CHG_DISK_OPTS, 28,
GENL_doit(drbd_adm_disk_opts),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED)
GENL_tla_expected(DRBD_NLA_DISK_OPTS, DRBD_F_REQUIRED)
)
GENL_op(
DRBD_ADM_RESIZE, 13,
GENL_doit(drbd_adm_resize),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED)
GENL_tla_expected(DRBD_NLA_RESIZE_PARMS, DRBD_GENLA_F_MANDATORY)
)
GENL_op(
DRBD_ADM_PRIMARY, 14,
GENL_doit(drbd_adm_set_role),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED)
GENL_tla_expected(DRBD_NLA_SET_ROLE_PARMS, DRBD_F_REQUIRED)
)
GENL_op(
DRBD_ADM_SECONDARY, 15,
GENL_doit(drbd_adm_set_role),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED)
GENL_tla_expected(DRBD_NLA_SET_ROLE_PARMS, DRBD_F_REQUIRED)
)
GENL_op(
DRBD_ADM_NEW_C_UUID, 16,
GENL_doit(drbd_adm_new_c_uuid),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED)
GENL_tla_expected(DRBD_NLA_NEW_C_UUID_PARMS, DRBD_GENLA_F_MANDATORY)
)
GENL_op(
DRBD_ADM_START_OV, 17,
GENL_doit(drbd_adm_start_ov),
GENL_tla_expected(DRBD_NLA_START_OV_PARMS, DRBD_GENLA_F_MANDATORY)
)
GENL_op(DRBD_ADM_DETACH, 18, GENL_doit(drbd_adm_detach),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED)
GENL_tla_expected(DRBD_NLA_DETACH_PARMS, DRBD_GENLA_F_MANDATORY))
GENL_op(DRBD_ADM_INVALIDATE, 19, GENL_doit(drbd_adm_invalidate),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED))
GENL_op(DRBD_ADM_INVAL_PEER, 20, GENL_doit(drbd_adm_invalidate_peer),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED))
GENL_op(DRBD_ADM_PAUSE_SYNC, 21, GENL_doit(drbd_adm_pause_sync),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED))
GENL_op(DRBD_ADM_RESUME_SYNC, 22, GENL_doit(drbd_adm_resume_sync),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED))
GENL_op(DRBD_ADM_SUSPEND_IO, 23, GENL_doit(drbd_adm_suspend_io),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED))
GENL_op(DRBD_ADM_RESUME_IO, 24, GENL_doit(drbd_adm_resume_io),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED))
GENL_op(DRBD_ADM_OUTDATE, 25, GENL_doit(drbd_adm_outdate),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED))
GENL_op(DRBD_ADM_GET_TIMEOUT_TYPE, 26, GENL_doit(drbd_adm_get_timeout_type),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED))
GENL_op(DRBD_ADM_DOWN, 27, GENL_doit(drbd_adm_down),
GENL_tla_expected(DRBD_NLA_CFG_CONTEXT, DRBD_F_REQUIRED))
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