diff options
Diffstat (limited to 'drivers/block/drbd/drbd_state.c')
| -rw-r--r-- | drivers/block/drbd/drbd_state.c | 1918 |
1 files changed, 1918 insertions, 0 deletions
diff --git a/drivers/block/drbd/drbd_state.c b/drivers/block/drbd/drbd_state.c new file mode 100644 index 000000000..2d7dd269b --- /dev/null +++ b/drivers/block/drbd/drbd_state.c @@ -0,0 +1,1918 @@ +/* + drbd_state.c + + This file is part of DRBD by Philipp Reisner and Lars Ellenberg. + + Copyright (C) 2001-2008, LINBIT Information Technologies GmbH. + Copyright (C) 1999-2008, Philipp Reisner <philipp.reisner@linbit.com>. + Copyright (C) 2002-2008, Lars Ellenberg <lars.ellenberg@linbit.com>. + + Thanks to Carter Burden, Bart Grantham and Gennadiy Nerubayev + from Logicworks, Inc. for making SDP replication support possible. + + drbd is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + drbd is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with drbd; see the file COPYING. If not, write to + the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include <linux/drbd_limits.h> +#include "drbd_int.h" +#include "drbd_protocol.h" +#include "drbd_req.h" + +struct after_state_chg_work { + struct drbd_work w; + struct drbd_device *device; + union drbd_state os; + union drbd_state ns; + enum chg_state_flags flags; + struct completion *done; +}; + +enum sanitize_state_warnings { + NO_WARNING, + ABORTED_ONLINE_VERIFY, + ABORTED_RESYNC, + CONNECTION_LOST_NEGOTIATING, + IMPLICITLY_UPGRADED_DISK, + IMPLICITLY_UPGRADED_PDSK, +}; + +static int w_after_state_ch(struct drbd_work *w, int unused); +static void after_state_ch(struct drbd_device *device, union drbd_state os, + union drbd_state ns, enum chg_state_flags flags); +static enum drbd_state_rv is_valid_state(struct drbd_device *, union drbd_state); +static enum drbd_state_rv is_valid_soft_transition(union drbd_state, union drbd_state, struct drbd_connection *); +static enum drbd_state_rv is_valid_transition(union drbd_state os, union drbd_state ns); +static union drbd_state sanitize_state(struct drbd_device *device, union drbd_state os, + union drbd_state ns, enum sanitize_state_warnings *warn); + +static inline bool is_susp(union drbd_state s) +{ + return s.susp || s.susp_nod || s.susp_fen; +} + +bool conn_all_vols_unconf(struct drbd_connection *connection) +{ + struct drbd_peer_device *peer_device; + bool rv = true; + int vnr; + + rcu_read_lock(); + idr_for_each_entry(&connection->peer_devices, peer_device, vnr) { + struct drbd_device *device = peer_device->device; + if (device->state.disk != D_DISKLESS || + device->state.conn != C_STANDALONE || + device->state.role != R_SECONDARY) { + rv = false; + break; + } + } + rcu_read_unlock(); + + return rv; +} + +/* Unfortunately the states where not correctly ordered, when + they where defined. therefore can not use max_t() here. */ +static enum drbd_role max_role(enum drbd_role role1, enum drbd_role role2) +{ + if (role1 == R_PRIMARY || role2 == R_PRIMARY) + return R_PRIMARY; + if (role1 == R_SECONDARY || role2 == R_SECONDARY) + return R_SECONDARY; + return R_UNKNOWN; +} +static enum drbd_role min_role(enum drbd_role role1, enum drbd_role role2) +{ + if (role1 == R_UNKNOWN || role2 == R_UNKNOWN) + return R_UNKNOWN; + if (role1 == R_SECONDARY || role2 == R_SECONDARY) + return R_SECONDARY; + return R_PRIMARY; +} + +enum drbd_role conn_highest_role(struct drbd_connection *connection) +{ + enum drbd_role role = R_UNKNOWN; + struct drbd_peer_device *peer_device; + int vnr; + + rcu_read_lock(); + idr_for_each_entry(&connection->peer_devices, peer_device, vnr) { + struct drbd_device *device = peer_device->device; + role = max_role(role, device->state.role); + } + rcu_read_unlock(); + + return role; +} + +enum drbd_role conn_highest_peer(struct drbd_connection *connection) +{ + enum drbd_role peer = R_UNKNOWN; + struct drbd_peer_device *peer_device; + int vnr; + + rcu_read_lock(); + idr_for_each_entry(&connection->peer_devices, peer_device, vnr) { + struct drbd_device *device = peer_device->device; + peer = max_role(peer, device->state.peer); + } + rcu_read_unlock(); + + return peer; +} + +enum drbd_disk_state conn_highest_disk(struct drbd_connection *connection) +{ + enum drbd_disk_state disk_state = D_DISKLESS; + struct drbd_peer_device *peer_device; + int vnr; + + rcu_read_lock(); + idr_for_each_entry(&connection->peer_devices, peer_device, vnr) { + struct drbd_device *device = peer_device->device; + disk_state = max_t(enum drbd_disk_state, disk_state, device->state.disk); + } + rcu_read_unlock(); + + return disk_state; +} + +enum drbd_disk_state conn_lowest_disk(struct drbd_connection *connection) +{ + enum drbd_disk_state disk_state = D_MASK; + struct drbd_peer_device *peer_device; + int vnr; + + rcu_read_lock(); + idr_for_each_entry(&connection->peer_devices, peer_device, vnr) { + struct drbd_device *device = peer_device->device; + disk_state = min_t(enum drbd_disk_state, disk_state, device->state.disk); + } + rcu_read_unlock(); + + return disk_state; +} + +enum drbd_disk_state conn_highest_pdsk(struct drbd_connection *connection) +{ + enum drbd_disk_state disk_state = D_DISKLESS; + struct drbd_peer_device *peer_device; + int vnr; + + rcu_read_lock(); + idr_for_each_entry(&connection->peer_devices, peer_device, vnr) { + struct drbd_device *device = peer_device->device; + disk_state = max_t(enum drbd_disk_state, disk_state, device->state.pdsk); + } + rcu_read_unlock(); + + return disk_state; +} + +enum drbd_conns conn_lowest_conn(struct drbd_connection *connection) +{ + enum drbd_conns conn = C_MASK; + struct drbd_peer_device *peer_device; + int vnr; + + rcu_read_lock(); + idr_for_each_entry(&connection->peer_devices, peer_device, vnr) { + struct drbd_device *device = peer_device->device; + conn = min_t(enum drbd_conns, conn, device->state.conn); + } + rcu_read_unlock(); + + return conn; +} + +static bool no_peer_wf_report_params(struct drbd_connection *connection) +{ + struct drbd_peer_device *peer_device; + int vnr; + bool rv = true; + + rcu_read_lock(); + idr_for_each_entry(&connection->peer_devices, peer_device, vnr) + if (peer_device->device->state.conn == C_WF_REPORT_PARAMS) { + rv = false; + break; + } + rcu_read_unlock(); + + return rv; +} + +static void wake_up_all_devices(struct drbd_connection *connection) +{ + struct drbd_peer_device *peer_device; + int vnr; + + rcu_read_lock(); + idr_for_each_entry(&connection->peer_devices, peer_device, vnr) + wake_up(&peer_device->device->state_wait); + rcu_read_unlock(); + +} + + +/** + * cl_wide_st_chg() - true if the state change is a cluster wide one + * @device: DRBD device. + * @os: old (current) state. + * @ns: new (wanted) state. + */ +static int cl_wide_st_chg(struct drbd_device *device, + union drbd_state os, union drbd_state ns) +{ + return (os.conn >= C_CONNECTED && ns.conn >= C_CONNECTED && + ((os.role != R_PRIMARY && ns.role == R_PRIMARY) || + (os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) || + (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S) || + (os.disk != D_FAILED && ns.disk == D_FAILED))) || + (os.conn >= C_CONNECTED && ns.conn == C_DISCONNECTING) || + (os.conn == C_CONNECTED && ns.conn == C_VERIFY_S) || + (os.conn == C_CONNECTED && ns.conn == C_WF_REPORT_PARAMS); +} + +static union drbd_state +apply_mask_val(union drbd_state os, union drbd_state mask, union drbd_state val) +{ + union drbd_state ns; + ns.i = (os.i & ~mask.i) | val.i; + return ns; +} + +enum drbd_state_rv +drbd_change_state(struct drbd_device *device, enum chg_state_flags f, + union drbd_state mask, union drbd_state val) +{ + unsigned long flags; + union drbd_state ns; + enum drbd_state_rv rv; + + spin_lock_irqsave(&device->resource->req_lock, flags); + ns = apply_mask_val(drbd_read_state(device), mask, val); + rv = _drbd_set_state(device, ns, f, NULL); + spin_unlock_irqrestore(&device->resource->req_lock, flags); + + return rv; +} + +/** + * drbd_force_state() - Impose a change which happens outside our control on our state + * @device: DRBD device. + * @mask: mask of state bits to change. + * @val: value of new state bits. + */ +void drbd_force_state(struct drbd_device *device, + union drbd_state mask, union drbd_state val) +{ + drbd_change_state(device, CS_HARD, mask, val); +} + +static enum drbd_state_rv +_req_st_cond(struct drbd_device *device, union drbd_state mask, + union drbd_state val) +{ + union drbd_state os, ns; + unsigned long flags; + enum drbd_state_rv rv; + + if (test_and_clear_bit(CL_ST_CHG_SUCCESS, &device->flags)) + return SS_CW_SUCCESS; + + if (test_and_clear_bit(CL_ST_CHG_FAIL, &device->flags)) + return SS_CW_FAILED_BY_PEER; + + spin_lock_irqsave(&device->resource->req_lock, flags); + os = drbd_read_state(device); + ns = sanitize_state(device, os, apply_mask_val(os, mask, val), NULL); + rv = is_valid_transition(os, ns); + if (rv >= SS_SUCCESS) + rv = SS_UNKNOWN_ERROR; /* cont waiting, otherwise fail. */ + + if (!cl_wide_st_chg(device, os, ns)) + rv = SS_CW_NO_NEED; + if (rv == SS_UNKNOWN_ERROR) { + rv = is_valid_state(device, ns); + if (rv >= SS_SUCCESS) { + rv = is_valid_soft_transition(os, ns, first_peer_device(device)->connection); + if (rv >= SS_SUCCESS) + rv = SS_UNKNOWN_ERROR; /* cont waiting, otherwise fail. */ + } + } + spin_unlock_irqrestore(&device->resource->req_lock, flags); + + return rv; +} + +/** + * drbd_req_state() - Perform an eventually cluster wide state change + * @device: DRBD device. + * @mask: mask of state bits to change. + * @val: value of new state bits. + * @f: flags + * + * Should not be called directly, use drbd_request_state() or + * _drbd_request_state(). + */ +static enum drbd_state_rv +drbd_req_state(struct drbd_device *device, union drbd_state mask, + union drbd_state val, enum chg_state_flags f) +{ + struct completion done; + unsigned long flags; + union drbd_state os, ns; + enum drbd_state_rv rv; + + init_completion(&done); + + if (f & CS_SERIALIZE) + mutex_lock(device->state_mutex); + + spin_lock_irqsave(&device->resource->req_lock, flags); + os = drbd_read_state(device); + ns = sanitize_state(device, os, apply_mask_val(os, mask, val), NULL); + rv = is_valid_transition(os, ns); + if (rv < SS_SUCCESS) { + spin_unlock_irqrestore(&device->resource->req_lock, flags); + goto abort; + } + + if (cl_wide_st_chg(device, os, ns)) { + rv = is_valid_state(device, ns); + if (rv == SS_SUCCESS) + rv = is_valid_soft_transition(os, ns, first_peer_device(device)->connection); + spin_unlock_irqrestore(&device->resource->req_lock, flags); + + if (rv < SS_SUCCESS) { + if (f & CS_VERBOSE) + print_st_err(device, os, ns, rv); + goto abort; + } + + if (drbd_send_state_req(first_peer_device(device), mask, val)) { + rv = SS_CW_FAILED_BY_PEER; + if (f & CS_VERBOSE) + print_st_err(device, os, ns, rv); + goto abort; + } + + wait_event(device->state_wait, + (rv = _req_st_cond(device, mask, val))); + + if (rv < SS_SUCCESS) { + if (f & CS_VERBOSE) + print_st_err(device, os, ns, rv); + goto abort; + } + spin_lock_irqsave(&device->resource->req_lock, flags); + ns = apply_mask_val(drbd_read_state(device), mask, val); + rv = _drbd_set_state(device, ns, f, &done); + } else { + rv = _drbd_set_state(device, ns, f, &done); + } + + spin_unlock_irqrestore(&device->resource->req_lock, flags); + + if (f & CS_WAIT_COMPLETE && rv == SS_SUCCESS) { + D_ASSERT(device, current != first_peer_device(device)->connection->worker.task); + wait_for_completion(&done); + } + +abort: + if (f & CS_SERIALIZE) + mutex_unlock(device->state_mutex); + + return rv; +} + +/** + * _drbd_request_state() - Request a state change (with flags) + * @device: DRBD device. + * @mask: mask of state bits to change. + * @val: value of new state bits. + * @f: flags + * + * Cousin of drbd_request_state(), useful with the CS_WAIT_COMPLETE + * flag, or when logging of failed state change requests is not desired. + */ +enum drbd_state_rv +_drbd_request_state(struct drbd_device *device, union drbd_state mask, + union drbd_state val, enum chg_state_flags f) +{ + enum drbd_state_rv rv; + + wait_event(device->state_wait, + (rv = drbd_req_state(device, mask, val, f)) != SS_IN_TRANSIENT_STATE); + + return rv; +} + +enum drbd_state_rv +_drbd_request_state_holding_state_mutex(struct drbd_device *device, union drbd_state mask, + union drbd_state val, enum chg_state_flags f) +{ + enum drbd_state_rv rv; + + BUG_ON(f & CS_SERIALIZE); + + wait_event_cmd(device->state_wait, + (rv = drbd_req_state(device, mask, val, f)) != SS_IN_TRANSIENT_STATE, + mutex_unlock(device->state_mutex), + mutex_lock(device->state_mutex)); + + return rv; +} + +static void print_st(struct drbd_device *device, const char *name, union drbd_state ns) +{ + drbd_err(device, " %s = { cs:%s ro:%s/%s ds:%s/%s %c%c%c%c%c%c }\n", + name, + drbd_conn_str(ns.conn), + drbd_role_str(ns.role), + drbd_role_str(ns.peer), + drbd_disk_str(ns.disk), + drbd_disk_str(ns.pdsk), + is_susp(ns) ? 's' : 'r', + ns.aftr_isp ? 'a' : '-', + ns.peer_isp ? 'p' : '-', + ns.user_isp ? 'u' : '-', + ns.susp_fen ? 'F' : '-', + ns.susp_nod ? 'N' : '-' + ); +} + +void print_st_err(struct drbd_device *device, union drbd_state os, + union drbd_state ns, enum drbd_state_rv err) +{ + if (err == SS_IN_TRANSIENT_STATE) + return; + drbd_err(device, "State change failed: %s\n", drbd_set_st_err_str(err)); + print_st(device, " state", os); + print_st(device, "wanted", ns); +} + +static long print_state_change(char *pb, union drbd_state os, union drbd_state ns, + enum chg_state_flags flags) +{ + char *pbp; + pbp = pb; + *pbp = 0; + + if (ns.role != os.role && flags & CS_DC_ROLE) + pbp += sprintf(pbp, "role( %s -> %s ) ", + drbd_role_str(os.role), + drbd_role_str(ns.role)); + if (ns.peer != os.peer && flags & CS_DC_PEER) + pbp += sprintf(pbp, "peer( %s -> %s ) ", + drbd_role_str(os.peer), + drbd_role_str(ns.peer)); + if (ns.conn != os.conn && flags & CS_DC_CONN) + pbp += sprintf(pbp, "conn( %s -> %s ) ", + drbd_conn_str(os.conn), + drbd_conn_str(ns.conn)); + if (ns.disk != os.disk && flags & CS_DC_DISK) + pbp += sprintf(pbp, "disk( %s -> %s ) ", + drbd_disk_str(os.disk), + drbd_disk_str(ns.disk)); + if (ns.pdsk != os.pdsk && flags & CS_DC_PDSK) + pbp += sprintf(pbp, "pdsk( %s -> %s ) ", + drbd_disk_str(os.pdsk), + drbd_disk_str(ns.pdsk)); + + return pbp - pb; +} + +static void drbd_pr_state_change(struct drbd_device *device, union drbd_state os, union drbd_state ns, + enum chg_state_flags flags) +{ + char pb[300]; + char *pbp = pb; + + pbp += print_state_change(pbp, os, ns, flags ^ CS_DC_MASK); + + if (ns.aftr_isp != os.aftr_isp) + pbp += sprintf(pbp, "aftr_isp( %d -> %d ) ", + os.aftr_isp, + ns.aftr_isp); + if (ns.peer_isp != os.peer_isp) + pbp += sprintf(pbp, "peer_isp( %d -> %d ) ", + os.peer_isp, + ns.peer_isp); + if (ns.user_isp != os.user_isp) + pbp += sprintf(pbp, "user_isp( %d -> %d ) ", + os.user_isp, + ns.user_isp); + + if (pbp != pb) + drbd_info(device, "%s\n", pb); +} + +static void conn_pr_state_change(struct drbd_connection *connection, union drbd_state os, union drbd_state ns, + enum chg_state_flags flags) +{ + char pb[300]; + char *pbp = pb; + + pbp += print_state_change(pbp, os, ns, flags); + + if (is_susp(ns) != is_susp(os) && flags & CS_DC_SUSP) + pbp += sprintf(pbp, "susp( %d -> %d ) ", + is_susp(os), + is_susp(ns)); + + if (pbp != pb) + drbd_info(connection, "%s\n", pb); +} + + +/** + * is_valid_state() - Returns an SS_ error code if ns is not valid + * @device: DRBD device. + * @ns: State to consider. + */ +static enum drbd_state_rv +is_valid_state(struct drbd_device *device, union drbd_state ns) +{ + /* See drbd_state_sw_errors in drbd_strings.c */ + + enum drbd_fencing_p fp; + enum drbd_state_rv rv = SS_SUCCESS; + struct net_conf *nc; + + rcu_read_lock(); + fp = FP_DONT_CARE; + if (get_ldev(device)) { + fp = rcu_dereference(device->ldev->disk_conf)->fencing; + put_ldev(device); + } + + nc = rcu_dereference(first_peer_device(device)->connection->net_conf); + if (nc) { + if (!nc->two_primaries && ns.role == R_PRIMARY) { + if (ns.peer == R_PRIMARY) + rv = SS_TWO_PRIMARIES; + else if (conn_highest_peer(first_peer_device(device)->connection) == R_PRIMARY) + rv = SS_O_VOL_PEER_PRI; + } + } + + if (rv <= 0) + /* already found a reason to abort */; + else if (ns.role == R_SECONDARY && device->open_cnt) + rv = SS_DEVICE_IN_USE; + + else if (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.disk < D_UP_TO_DATE) + rv = SS_NO_UP_TO_DATE_DISK; + + else if (fp >= FP_RESOURCE && + ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk >= D_UNKNOWN) + rv = SS_PRIMARY_NOP; + + else if (ns.role == R_PRIMARY && ns.disk <= D_INCONSISTENT && ns.pdsk <= D_INCONSISTENT) + rv = SS_NO_UP_TO_DATE_DISK; + + else if (ns.conn > C_CONNECTED && ns.disk < D_INCONSISTENT) + rv = SS_NO_LOCAL_DISK; + + else if (ns.conn > C_CONNECTED && ns.pdsk < D_INCONSISTENT) + rv = SS_NO_REMOTE_DISK; + + else if (ns.conn > C_CONNECTED && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE) + rv = SS_NO_UP_TO_DATE_DISK; + + else if ((ns.conn == C_CONNECTED || + ns.conn == C_WF_BITMAP_S || + ns.conn == C_SYNC_SOURCE || + ns.conn == C_PAUSED_SYNC_S) && + ns.disk == D_OUTDATED) + rv = SS_CONNECTED_OUTDATES; + + else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) && + (nc->verify_alg[0] == 0)) + rv = SS_NO_VERIFY_ALG; + + else if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) && + first_peer_device(device)->connection->agreed_pro_version < 88) + rv = SS_NOT_SUPPORTED; + + else if (ns.role == R_PRIMARY && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE) + rv = SS_NO_UP_TO_DATE_DISK; + + else if ((ns.conn == C_STARTING_SYNC_S || ns.conn == C_STARTING_SYNC_T) && + ns.pdsk == D_UNKNOWN) + rv = SS_NEED_CONNECTION; + + else if (ns.conn >= C_CONNECTED && ns.pdsk == D_UNKNOWN) + rv = SS_CONNECTED_OUTDATES; + + rcu_read_unlock(); + + return rv; +} + +/** + * is_valid_soft_transition() - Returns an SS_ error code if the state transition is not possible + * This function limits state transitions that may be declined by DRBD. I.e. + * user requests (aka soft transitions). + * @device: DRBD device. + * @ns: new state. + * @os: old state. + */ +static enum drbd_state_rv +is_valid_soft_transition(union drbd_state os, union drbd_state ns, struct drbd_connection *connection) +{ + enum drbd_state_rv rv = SS_SUCCESS; + + if ((ns.conn == C_STARTING_SYNC_T || ns.conn == C_STARTING_SYNC_S) && + os.conn > C_CONNECTED) + rv = SS_RESYNC_RUNNING; + + if (ns.conn == C_DISCONNECTING && os.conn == C_STANDALONE) + rv = SS_ALREADY_STANDALONE; + + if (ns.disk > D_ATTACHING && os.disk == D_DISKLESS) + rv = SS_IS_DISKLESS; + + if (ns.conn == C_WF_CONNECTION && os.conn < C_UNCONNECTED) + rv = SS_NO_NET_CONFIG; + + if (ns.disk == D_OUTDATED && os.disk < D_OUTDATED && os.disk != D_ATTACHING) + rv = SS_LOWER_THAN_OUTDATED; + + if (ns.conn == C_DISCONNECTING && os.conn == C_UNCONNECTED) + rv = SS_IN_TRANSIENT_STATE; + + /* While establishing a connection only allow cstate to change. + Delay/refuse role changes, detach attach etc... (they do not touch cstate) */ + if (test_bit(STATE_SENT, &connection->flags) && + !((ns.conn == C_WF_REPORT_PARAMS && os.conn == C_WF_CONNECTION) || + (ns.conn >= C_CONNECTED && os.conn == C_WF_REPORT_PARAMS))) + rv = SS_IN_TRANSIENT_STATE; + + if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) && os.conn < C_CONNECTED) + rv = SS_NEED_CONNECTION; + + if ((ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T) && + ns.conn != os.conn && os.conn > C_CONNECTED) + rv = SS_RESYNC_RUNNING; + + if ((ns.conn == C_STARTING_SYNC_S || ns.conn == C_STARTING_SYNC_T) && + os.conn < C_CONNECTED) + rv = SS_NEED_CONNECTION; + + if ((ns.conn == C_SYNC_TARGET || ns.conn == C_SYNC_SOURCE) + && os.conn < C_WF_REPORT_PARAMS) + rv = SS_NEED_CONNECTION; /* No NetworkFailure -> SyncTarget etc... */ + + if (ns.conn == C_DISCONNECTING && ns.pdsk == D_OUTDATED && + os.conn < C_CONNECTED && os.pdsk > D_OUTDATED) + rv = SS_OUTDATE_WO_CONN; + + return rv; +} + +static enum drbd_state_rv +is_valid_conn_transition(enum drbd_conns oc, enum drbd_conns nc) +{ + /* no change -> nothing to do, at least for the connection part */ + if (oc == nc) + return SS_NOTHING_TO_DO; + + /* disconnect of an unconfigured connection does not make sense */ + if (oc == C_STANDALONE && nc == C_DISCONNECTING) + return SS_ALREADY_STANDALONE; + + /* from C_STANDALONE, we start with C_UNCONNECTED */ + if (oc == C_STANDALONE && nc != C_UNCONNECTED) + return SS_NEED_CONNECTION; + + /* When establishing a connection we need to go through WF_REPORT_PARAMS! + Necessary to do the right thing upon invalidate-remote on a disconnected resource */ + if (oc < C_WF_REPORT_PARAMS && nc >= C_CONNECTED) + return SS_NEED_CONNECTION; + + /* After a network error only C_UNCONNECTED or C_DISCONNECTING may follow. */ + if (oc >= C_TIMEOUT && oc <= C_TEAR_DOWN && nc != C_UNCONNECTED && nc != C_DISCONNECTING) + return SS_IN_TRANSIENT_STATE; + + /* After C_DISCONNECTING only C_STANDALONE may follow */ + if (oc == C_DISCONNECTING && nc != C_STANDALONE) + return SS_IN_TRANSIENT_STATE; + + return SS_SUCCESS; +} + + +/** + * is_valid_transition() - Returns an SS_ error code if the state transition is not possible + * This limits hard state transitions. Hard state transitions are facts there are + * imposed on DRBD by the environment. E.g. disk broke or network broke down. + * But those hard state transitions are still not allowed to do everything. + * @ns: new state. + * @os: old state. + */ +static enum drbd_state_rv +is_valid_transition(union drbd_state os, union drbd_state ns) +{ + enum drbd_state_rv rv; + + rv = is_valid_conn_transition(os.conn, ns.conn); + + /* we cannot fail (again) if we already detached */ + if (ns.disk == D_FAILED && os.disk == D_DISKLESS) + rv = SS_IS_DISKLESS; + + return rv; +} + +static void print_sanitize_warnings(struct drbd_device *device, enum sanitize_state_warnings warn) +{ + static const char *msg_table[] = { + [NO_WARNING] = "", + [ABORTED_ONLINE_VERIFY] = "Online-verify aborted.", + [ABORTED_RESYNC] = "Resync aborted.", + [CONNECTION_LOST_NEGOTIATING] = "Connection lost while negotiating, no data!", + [IMPLICITLY_UPGRADED_DISK] = "Implicitly upgraded disk", + [IMPLICITLY_UPGRADED_PDSK] = "Implicitly upgraded pdsk", + }; + + if (warn != NO_WARNING) + drbd_warn(device, "%s\n", msg_table[warn]); +} + +/** + * sanitize_state() - Resolves implicitly necessary additional changes to a state transition + * @device: DRBD device. + * @os: old state. + * @ns: new state. + * @warn_sync_abort: + * + * When we loose connection, we have to set the state of the peers disk (pdsk) + * to D_UNKNOWN. This rule and many more along those lines are in this function. + */ +static union drbd_state sanitize_state(struct drbd_device *device, union drbd_state os, + union drbd_state ns, enum sanitize_state_warnings *warn) +{ + enum drbd_fencing_p fp; + enum drbd_disk_state disk_min, disk_max, pdsk_min, pdsk_max; + + if (warn) + *warn = NO_WARNING; + + fp = FP_DONT_CARE; + if (get_ldev(device)) { + rcu_read_lock(); + fp = rcu_dereference(device->ldev->disk_conf)->fencing; + rcu_read_unlock(); + put_ldev(device); + } + + /* Implications from connection to peer and peer_isp */ + if (ns.conn < C_CONNECTED) { + ns.peer_isp = 0; + ns.peer = R_UNKNOWN; + if (ns.pdsk > D_UNKNOWN || ns.pdsk < D_INCONSISTENT) + ns.pdsk = D_UNKNOWN; + } + + /* Clear the aftr_isp when becoming unconfigured */ + if (ns.conn == C_STANDALONE && ns.disk == D_DISKLESS && ns.role == R_SECONDARY) + ns.aftr_isp = 0; + + /* An implication of the disk states onto the connection state */ + /* Abort resync if a disk fails/detaches */ + if (ns.conn > C_CONNECTED && (ns.disk <= D_FAILED || ns.pdsk <= D_FAILED)) { + if (warn) + *warn = ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T ? + ABORTED_ONLINE_VERIFY : ABORTED_RESYNC; + ns.conn = C_CONNECTED; + } + + /* Connection breaks down before we finished "Negotiating" */ + if (ns.conn < C_CONNECTED && ns.disk == D_NEGOTIATING && + get_ldev_if_state(device, D_NEGOTIATING)) { + if (device->ed_uuid == device->ldev->md.uuid[UI_CURRENT]) { + ns.disk = device->new_state_tmp.disk; + ns.pdsk = device->new_state_tmp.pdsk; + } else { + if (warn) + *warn = CONNECTION_LOST_NEGOTIATING; + ns.disk = D_DISKLESS; + ns.pdsk = D_UNKNOWN; + } + put_ldev(device); + } + + /* D_CONSISTENT and D_OUTDATED vanish when we get connected */ + if (ns.conn >= C_CONNECTED && ns.conn < C_AHEAD) { + if (ns.disk == D_CONSISTENT || ns.disk == D_OUTDATED) + ns.disk = D_UP_TO_DATE; + if (ns.pdsk == D_CONSISTENT || ns.pdsk == D_OUTDATED) + ns.pdsk = D_UP_TO_DATE; + } + + /* Implications of the connection stat on the disk states */ + disk_min = D_DISKLESS; + disk_max = D_UP_TO_DATE; + pdsk_min = D_INCONSISTENT; + pdsk_max = D_UNKNOWN; + switch ((enum drbd_conns)ns.conn) { + case C_WF_BITMAP_T: + case C_PAUSED_SYNC_T: + case C_STARTING_SYNC_T: + case C_WF_SYNC_UUID: + case C_BEHIND: + disk_min = D_INCONSISTENT; + disk_max = D_OUTDATED; + pdsk_min = D_UP_TO_DATE; + pdsk_max = D_UP_TO_DATE; + break; + case C_VERIFY_S: + case C_VERIFY_T: + disk_min = D_UP_TO_DATE; + disk_max = D_UP_TO_DATE; + pdsk_min = D_UP_TO_DATE; + pdsk_max = D_UP_TO_DATE; + break; + case C_CONNECTED: + disk_min = D_DISKLESS; + disk_max = D_UP_TO_DATE; + pdsk_min = D_DISKLESS; + pdsk_max = D_UP_TO_DATE; + break; + case C_WF_BITMAP_S: + case C_PAUSED_SYNC_S: + case C_STARTING_SYNC_S: + case C_AHEAD: + disk_min = D_UP_TO_DATE; + disk_max = D_UP_TO_DATE; + pdsk_min = D_INCONSISTENT; + pdsk_max = D_CONSISTENT; /* D_OUTDATED would be nice. But explicit outdate necessary*/ + break; + case C_SYNC_TARGET: + disk_min = D_INCONSISTENT; + disk_max = D_INCONSISTENT; + pdsk_min = D_UP_TO_DATE; + pdsk_max = D_UP_TO_DATE; + break; + case C_SYNC_SOURCE: + disk_min = D_UP_TO_DATE; + disk_max = D_UP_TO_DATE; + pdsk_min = D_INCONSISTENT; + pdsk_max = D_INCONSISTENT; + break; + case C_STANDALONE: + case C_DISCONNECTING: + case C_UNCONNECTED: + case C_TIMEOUT: + case C_BROKEN_PIPE: + case C_NETWORK_FAILURE: + case C_PROTOCOL_ERROR: + case C_TEAR_DOWN: + case C_WF_CONNECTION: + case C_WF_REPORT_PARAMS: + case C_MASK: + break; + } + if (ns.disk > disk_max) + ns.disk = disk_max; + + if (ns.disk < disk_min) { + if (warn) + *warn = IMPLICITLY_UPGRADED_DISK; + ns.disk = disk_min; + } + if (ns.pdsk > pdsk_max) + ns.pdsk = pdsk_max; + + if (ns.pdsk < pdsk_min) { + if (warn) + *warn = IMPLICITLY_UPGRADED_PDSK; + ns.pdsk = pdsk_min; + } + + if (fp == FP_STONITH && + (ns.role == R_PRIMARY && ns.conn < C_CONNECTED && ns.pdsk > D_OUTDATED) && + !(os.role == R_PRIMARY && os.conn < C_CONNECTED && os.pdsk > D_OUTDATED)) + ns.susp_fen = 1; /* Suspend IO while fence-peer handler runs (peer lost) */ + + if (device->resource->res_opts.on_no_data == OND_SUSPEND_IO && + (ns.role == R_PRIMARY && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE) && + !(os.role == R_PRIMARY && os.disk < D_UP_TO_DATE && os.pdsk < D_UP_TO_DATE)) + ns.susp_nod = 1; /* Suspend IO while no data available (no accessible data available) */ + + if (ns.aftr_isp || ns.peer_isp || ns.user_isp) { + if (ns.conn == C_SYNC_SOURCE) + ns.conn = C_PAUSED_SYNC_S; + if (ns.conn == C_SYNC_TARGET) + ns.conn = C_PAUSED_SYNC_T; + } else { + if (ns.conn == C_PAUSED_SYNC_S) + ns.conn = C_SYNC_SOURCE; + if (ns.conn == C_PAUSED_SYNC_T) + ns.conn = C_SYNC_TARGET; + } + + return ns; +} + +void drbd_resume_al(struct drbd_device *device) +{ + if (test_and_clear_bit(AL_SUSPENDED, &device->flags)) + drbd_info(device, "Resumed AL updates\n"); +} + +/* helper for __drbd_set_state */ +static void set_ov_position(struct drbd_device *device, enum drbd_conns cs) +{ + if (first_peer_device(device)->connection->agreed_pro_version < 90) + device->ov_start_sector = 0; + device->rs_total = drbd_bm_bits(device); + device->ov_position = 0; + if (cs == C_VERIFY_T) { + /* starting online verify from an arbitrary position + * does not fit well into the existing protocol. + * on C_VERIFY_T, we initialize ov_left and friends + * implicitly in receive_DataRequest once the + * first P_OV_REQUEST is received */ + device->ov_start_sector = ~(sector_t)0; + } else { + unsigned long bit = BM_SECT_TO_BIT(device->ov_start_sector); + if (bit >= device->rs_total) { + device->ov_start_sector = + BM_BIT_TO_SECT(device->rs_total - 1); + device->rs_total = 1; + } else + device->rs_total -= bit; + device->ov_position = device->ov_start_sector; + } + device->ov_left = device->rs_total; +} + +/** + * __drbd_set_state() - Set a new DRBD state + * @device: DRBD device. + * @ns: new state. + * @flags: Flags + * @done: Optional completion, that will get completed after the after_state_ch() finished + * + * Caller needs to hold req_lock, and global_state_lock. Do not call directly. + */ +enum drbd_state_rv +__drbd_set_state(struct drbd_device *device, union drbd_state ns, + enum chg_state_flags flags, struct completion *done) +{ + struct drbd_peer_device *peer_device = first_peer_device(device); + struct drbd_connection *connection = peer_device ? peer_device->connection : NULL; + union drbd_state os; + enum drbd_state_rv rv = SS_SUCCESS; + enum sanitize_state_warnings ssw; + struct after_state_chg_work *ascw; + + os = drbd_read_state(device); + + ns = sanitize_state(device, os, ns, &ssw); + if (ns.i == os.i) + return SS_NOTHING_TO_DO; + + rv = is_valid_transition(os, ns); + if (rv < SS_SUCCESS) + return rv; + + if (!(flags & CS_HARD)) { + /* pre-state-change checks ; only look at ns */ + /* See drbd_state_sw_errors in drbd_strings.c */ + + rv = is_valid_state(device, ns); + if (rv < SS_SUCCESS) { + /* If the old state was illegal as well, then let + this happen...*/ + + if (is_valid_state(device, os) == rv) + rv = is_valid_soft_transition(os, ns, connection); + } else + rv = is_valid_soft_transition(os, ns, connection); + } + + if (rv < SS_SUCCESS) { + if (flags & CS_VERBOSE) + print_st_err(device, os, ns, rv); + return rv; + } + + print_sanitize_warnings(device, ssw); + + drbd_pr_state_change(device, os, ns, flags); + + /* Display changes to the susp* flags that where caused by the call to + sanitize_state(). Only display it here if we where not called from + _conn_request_state() */ + if (!(flags & CS_DC_SUSP)) + conn_pr_state_change(connection, os, ns, + (flags & ~CS_DC_MASK) | CS_DC_SUSP); + + /* if we are going -> D_FAILED or D_DISKLESS, grab one extra reference + * on the ldev here, to be sure the transition -> D_DISKLESS resp. + * drbd_ldev_destroy() won't happen before our corresponding + * after_state_ch works run, where we put_ldev again. */ + if ((os.disk != D_FAILED && ns.disk == D_FAILED) || + (os.disk != D_DISKLESS && ns.disk == D_DISKLESS)) + atomic_inc(&device->local_cnt); + + if (!is_sync_state(os.conn) && is_sync_state(ns.conn)) + clear_bit(RS_DONE, &device->flags); + + /* changes to local_cnt and device flags should be visible before + * changes to state, which again should be visible before anything else + * depending on that change happens. */ + smp_wmb(); + device->state.i = ns.i; + device->resource->susp = ns.susp; + device->resource->susp_nod = ns.susp_nod; + device->resource->susp_fen = ns.susp_fen; + smp_wmb(); + + /* put replicated vs not-replicated requests in seperate epochs */ + if (drbd_should_do_remote((union drbd_dev_state)os.i) != + drbd_should_do_remote((union drbd_dev_state)ns.i)) + start_new_tl_epoch(connection); + + if (os.disk == D_ATTACHING && ns.disk >= D_NEGOTIATING) + drbd_print_uuids(device, "attached to UUIDs"); + + /* Wake up role changes, that were delayed because of connection establishing */ + if (os.conn == C_WF_REPORT_PARAMS && ns.conn != C_WF_REPORT_PARAMS && + no_peer_wf_report_params(connection)) { + clear_bit(STATE_SENT, &connection->flags); + wake_up_all_devices(connection); + } + + wake_up(&device->misc_wait); + wake_up(&device->state_wait); + wake_up(&connection->ping_wait); + + /* Aborted verify run, or we reached the stop sector. + * Log the last position, unless end-of-device. */ + if ((os.conn == C_VERIFY_S || os.conn == C_VERIFY_T) && + ns.conn <= C_CONNECTED) { + device->ov_start_sector = + BM_BIT_TO_SECT(drbd_bm_bits(device) - device->ov_left); + if (device->ov_left) + drbd_info(device, "Online Verify reached sector %llu\n", + (unsigned long long)device->ov_start_sector); + } + + if ((os.conn == C_PAUSED_SYNC_T || os.conn == C_PAUSED_SYNC_S) && + (ns.conn == C_SYNC_TARGET || ns.conn == C_SYNC_SOURCE)) { + drbd_info(device, "Syncer continues.\n"); + device->rs_paused += (long)jiffies + -(long)device->rs_mark_time[device->rs_last_mark]; + if (ns.conn == C_SYNC_TARGET) + mod_timer(&device->resync_timer, jiffies); + } + + if ((os.conn == C_SYNC_TARGET || os.conn == C_SYNC_SOURCE) && + (ns.conn == C_PAUSED_SYNC_T || ns.conn == C_PAUSED_SYNC_S)) { + drbd_info(device, "Resync suspended\n"); + device->rs_mark_time[device->rs_last_mark] = jiffies; + } + + if (os.conn == C_CONNECTED && + (ns.conn == C_VERIFY_S || ns.conn == C_VERIFY_T)) { + unsigned long now = jiffies; + int i; + + set_ov_position(device, ns.conn); + device->rs_start = now; + device->rs_last_sect_ev = 0; + device->ov_last_oos_size = 0; + device->ov_last_oos_start = 0; + + for (i = 0; i < DRBD_SYNC_MARKS; i++) { + device->rs_mark_left[i] = device->ov_left; + device->rs_mark_time[i] = now; + } + + drbd_rs_controller_reset(device); + + if (ns.conn == C_VERIFY_S) { + drbd_info(device, "Starting Online Verify from sector %llu\n", + (unsigned long long)device->ov_position); + mod_timer(&device->resync_timer, jiffies); + } + } + + if (get_ldev(device)) { + u32 mdf = device->ldev->md.flags & ~(MDF_CONSISTENT|MDF_PRIMARY_IND| + MDF_CONNECTED_IND|MDF_WAS_UP_TO_DATE| + MDF_PEER_OUT_DATED|MDF_CRASHED_PRIMARY); + + mdf &= ~MDF_AL_CLEAN; + if (test_bit(CRASHED_PRIMARY, &device->flags)) + mdf |= MDF_CRASHED_PRIMARY; + if (device->state.role == R_PRIMARY || + (device->state.pdsk < D_INCONSISTENT && device->state.peer == R_PRIMARY)) + mdf |= MDF_PRIMARY_IND; + if (device->state.conn > C_WF_REPORT_PARAMS) + mdf |= MDF_CONNECTED_IND; + if (device->state.disk > D_INCONSISTENT) + mdf |= MDF_CONSISTENT; + if (device->state.disk > D_OUTDATED) + mdf |= MDF_WAS_UP_TO_DATE; + if (device->state.pdsk <= D_OUTDATED && device->state.pdsk >= D_INCONSISTENT) + mdf |= MDF_PEER_OUT_DATED; + if (mdf != device->ldev->md.flags) { + device->ldev->md.flags = mdf; + drbd_md_mark_dirty(device); + } + if (os.disk < D_CONSISTENT && ns.disk >= D_CONSISTENT) + drbd_set_ed_uuid(device, device->ldev->md.uuid[UI_CURRENT]); + put_ldev(device); + } + + /* Peer was forced D_UP_TO_DATE & R_PRIMARY, consider to resync */ + if (os.disk == D_INCONSISTENT && os.pdsk == D_INCONSISTENT && + os.peer == R_SECONDARY && ns.peer == R_PRIMARY) + set_bit(CONSIDER_RESYNC, &device->flags); + + /* Receiver should clean up itself */ + if (os.conn != C_DISCONNECTING && ns.conn == C_DISCONNECTING) + drbd_thread_stop_nowait(&connection->receiver); + + /* Now the receiver finished cleaning up itself, it should die */ + if (os.conn != C_STANDALONE && ns.conn == C_STANDALONE) + drbd_thread_stop_nowait(&connection->receiver); + + /* Upon network failure, we need to restart the receiver. */ + if (os.conn > C_WF_CONNECTION && + ns.conn <= C_TEAR_DOWN && ns.conn >= C_TIMEOUT) + drbd_thread_restart_nowait(&connection->receiver); + + /* Resume AL writing if we get a connection */ + if (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED) { + drbd_resume_al(device); + connection->connect_cnt++; + } + + /* remember last attach time so request_timer_fn() won't + * kill newly established sessions while we are still trying to thaw + * previously frozen IO */ + if ((os.disk == D_ATTACHING || os.disk == D_NEGOTIATING) && + ns.disk > D_NEGOTIATING) + device->last_reattach_jif = jiffies; + + ascw = kmalloc(sizeof(*ascw), GFP_ATOMIC); + if (ascw) { + ascw->os = os; + ascw->ns = ns; + ascw->flags = flags; + ascw->w.cb = w_after_state_ch; + ascw->device = device; + ascw->done = done; + drbd_queue_work(&connection->sender_work, + &ascw->w); + } else { + drbd_err(device, "Could not kmalloc an ascw\n"); + } + + return rv; +} + +static int w_after_state_ch(struct drbd_work *w, int unused) +{ + struct after_state_chg_work *ascw = + container_of(w, struct after_state_chg_work, w); + struct drbd_device *device = ascw->device; + + after_state_ch(device, ascw->os, ascw->ns, ascw->flags); + if (ascw->flags & CS_WAIT_COMPLETE) + complete(ascw->done); + kfree(ascw); + + return 0; +} + +static void abw_start_sync(struct drbd_device *device, int rv) +{ + if (rv) { + drbd_err(device, "Writing the bitmap failed not starting resync.\n"); + _drbd_request_state(device, NS(conn, C_CONNECTED), CS_VERBOSE); + return; + } + + switch (device->state.conn) { + case C_STARTING_SYNC_T: + _drbd_request_state(device, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE); + break; + case C_STARTING_SYNC_S: + drbd_start_resync(device, C_SYNC_SOURCE); + break; + } +} + +int drbd_bitmap_io_from_worker(struct drbd_device *device, + int (*io_fn)(struct drbd_device *), + char *why, enum bm_flag flags) +{ + int rv; + + D_ASSERT(device, current == first_peer_device(device)->connection->worker.task); + + /* open coded non-blocking drbd_suspend_io(device); */ + set_bit(SUSPEND_IO, &device->flags); + + drbd_bm_lock(device, why, flags); + rv = io_fn(device); + drbd_bm_unlock(device); + + drbd_resume_io(device); + + return rv; +} + +/** + * after_state_ch() - Perform after state change actions that may sleep + * @device: DRBD device. + * @os: old state. + * @ns: new state. + * @flags: Flags + */ +static void after_state_ch(struct drbd_device *device, union drbd_state os, + union drbd_state ns, enum chg_state_flags flags) +{ + struct drbd_resource *resource = device->resource; + struct drbd_peer_device *peer_device = first_peer_device(device); + struct drbd_connection *connection = peer_device ? peer_device->connection : NULL; + struct sib_info sib; + + sib.sib_reason = SIB_STATE_CHANGE; + sib.os = os; + sib.ns = ns; + + if ((os.disk != D_UP_TO_DATE || os.pdsk != D_UP_TO_DATE) + && (ns.disk == D_UP_TO_DATE && ns.pdsk == D_UP_TO_DATE)) { + clear_bit(CRASHED_PRIMARY, &device->flags); + if (device->p_uuid) + device->p_uuid[UI_FLAGS] &= ~((u64)2); + } + + /* Inform userspace about the change... */ + drbd_bcast_event(device, &sib); + + if (!(os.role == R_PRIMARY && os.disk < D_UP_TO_DATE && os.pdsk < D_UP_TO_DATE) && + (ns.role == R_PRIMARY && ns.disk < D_UP_TO_DATE && ns.pdsk < D_UP_TO_DATE)) + drbd_khelper(device, "pri-on-incon-degr"); + + /* Here we have the actions that are performed after a + state change. This function might sleep */ + + if (ns.susp_nod) { + enum drbd_req_event what = NOTHING; + + spin_lock_irq(&device->resource->req_lock); + if (os.conn < C_CONNECTED && conn_lowest_conn(connection) >= C_CONNECTED) + what = RESEND; + + if ((os.disk == D_ATTACHING || os.disk == D_NEGOTIATING) && + conn_lowest_disk(connection) > D_NEGOTIATING) + what = RESTART_FROZEN_DISK_IO; + + if (resource->susp_nod && what != NOTHING) { + _tl_restart(connection, what); + _conn_request_state(connection, + (union drbd_state) { { .susp_nod = 1 } }, + (union drbd_state) { { .susp_nod = 0 } }, + CS_VERBOSE); + } + spin_unlock_irq(&device->resource->req_lock); + } + + if (ns.susp_fen) { + spin_lock_irq(&device->resource->req_lock); + if (resource->susp_fen && conn_lowest_conn(connection) >= C_CONNECTED) { + /* case2: The connection was established again: */ + struct drbd_peer_device *peer_device; + int vnr; + + rcu_read_lock(); + idr_for_each_entry(&connection->peer_devices, peer_device, vnr) + clear_bit(NEW_CUR_UUID, &peer_device->device->flags); + rcu_read_unlock(); + _tl_restart(connection, RESEND); + _conn_request_state(connection, + (union drbd_state) { { .susp_fen = 1 } }, + (union drbd_state) { { .susp_fen = 0 } }, + CS_VERBOSE); + } + spin_unlock_irq(&device->resource->req_lock); + } + + /* Became sync source. With protocol >= 96, we still need to send out + * the sync uuid now. Need to do that before any drbd_send_state, or + * the other side may go "paused sync" before receiving the sync uuids, + * which is unexpected. */ + if ((os.conn != C_SYNC_SOURCE && os.conn != C_PAUSED_SYNC_S) && + (ns.conn == C_SYNC_SOURCE || ns.conn == C_PAUSED_SYNC_S) && + connection->agreed_pro_version >= 96 && get_ldev(device)) { + drbd_gen_and_send_sync_uuid(peer_device); + put_ldev(device); + } + + /* Do not change the order of the if above and the two below... */ + if (os.pdsk == D_DISKLESS && + ns.pdsk > D_DISKLESS && ns.pdsk != D_UNKNOWN) { /* attach on the peer */ + /* we probably will start a resync soon. + * make sure those things are properly reset. */ + device->rs_total = 0; + device->rs_failed = 0; + atomic_set(&device->rs_pending_cnt, 0); + drbd_rs_cancel_all(device); + + drbd_send_uuids(peer_device); + drbd_send_state(peer_device, ns); + } + /* No point in queuing send_bitmap if we don't have a connection + * anymore, so check also the _current_ state, not only the new state + * at the time this work was queued. */ + if (os.conn != C_WF_BITMAP_S && ns.conn == C_WF_BITMAP_S && + device->state.conn == C_WF_BITMAP_S) + drbd_queue_bitmap_io(device, &drbd_send_bitmap, NULL, + "send_bitmap (WFBitMapS)", + BM_LOCKED_TEST_ALLOWED); + + /* Lost contact to peer's copy of the data */ + if ((os.pdsk >= D_INCONSISTENT && + os.pdsk != D_UNKNOWN && + os.pdsk != D_OUTDATED) + && (ns.pdsk < D_INCONSISTENT || + ns.pdsk == D_UNKNOWN || + ns.pdsk == D_OUTDATED)) { + if (get_ldev(device)) { + if ((ns.role == R_PRIMARY || ns.peer == R_PRIMARY) && + device->ldev->md.uuid[UI_BITMAP] == 0 && ns.disk >= D_UP_TO_DATE) { + if (drbd_suspended(device)) { + set_bit(NEW_CUR_UUID, &device->flags); + } else { + drbd_uuid_new_current(device); + drbd_send_uuids(peer_device); + } + } + put_ldev(device); + } + } + + if (ns.pdsk < D_INCONSISTENT && get_ldev(device)) { + if (os.peer == R_SECONDARY && ns.peer == R_PRIMARY && + device->ldev->md.uuid[UI_BITMAP] == 0 && ns.disk >= D_UP_TO_DATE) { + drbd_uuid_new_current(device); + drbd_send_uuids(peer_device); + } + /* D_DISKLESS Peer becomes secondary */ + if (os.peer == R_PRIMARY && ns.peer == R_SECONDARY) + /* We may still be Primary ourselves. + * No harm done if the bitmap still changes, + * redirtied pages will follow later. */ + drbd_bitmap_io_from_worker(device, &drbd_bm_write, + "demote diskless peer", BM_LOCKED_SET_ALLOWED); + put_ldev(device); + } + + /* Write out all changed bits on demote. + * Though, no need to da that just yet + * if there is a resync going on still */ + if (os.role == R_PRIMARY && ns.role == R_SECONDARY && + device->state.conn <= C_CONNECTED && get_ldev(device)) { + /* No changes to the bitmap expected this time, so assert that, + * even though no harm was done if it did change. */ + drbd_bitmap_io_from_worker(device, &drbd_bm_write, + "demote", BM_LOCKED_TEST_ALLOWED); + put_ldev(device); + } + + /* Last part of the attaching process ... */ + if (ns.conn >= C_CONNECTED && + os.disk == D_ATTACHING && ns.disk == D_NEGOTIATING) { + drbd_send_sizes(peer_device, 0, 0); /* to start sync... */ + drbd_send_uuids(peer_device); + drbd_send_state(peer_device, ns); + } + + /* We want to pause/continue resync, tell peer. */ + if (ns.conn >= C_CONNECTED && + ((os.aftr_isp != ns.aftr_isp) || + (os.user_isp != ns.user_isp))) + drbd_send_state(peer_device, ns); + + /* In case one of the isp bits got set, suspend other devices. */ + if ((!os.aftr_isp && !os.peer_isp && !os.user_isp) && + (ns.aftr_isp || ns.peer_isp || ns.user_isp)) + suspend_other_sg(device); + + /* Make sure the peer gets informed about eventual state + changes (ISP bits) while we were in WFReportParams. */ + if (os.conn == C_WF_REPORT_PARAMS && ns.conn >= C_CONNECTED) + drbd_send_state(peer_device, ns); + + if (os.conn != C_AHEAD && ns.conn == C_AHEAD) + drbd_send_state(peer_device, ns); + + /* We are in the progress to start a full sync... */ + if ((os.conn != C_STARTING_SYNC_T && ns.conn == C_STARTING_SYNC_T) || + (os.conn != C_STARTING_SYNC_S && ns.conn == C_STARTING_SYNC_S)) + /* no other bitmap changes expected during this phase */ + drbd_queue_bitmap_io(device, + &drbd_bmio_set_n_write, &abw_start_sync, + "set_n_write from StartingSync", BM_LOCKED_TEST_ALLOWED); + + /* first half of local IO error, failure to attach, + * or administrative detach */ + if (os.disk != D_FAILED && ns.disk == D_FAILED) { + enum drbd_io_error_p eh = EP_PASS_ON; + int was_io_error = 0; + /* corresponding get_ldev was in __drbd_set_state, to serialize + * our cleanup here with the transition to D_DISKLESS. + * But is is still not save to dreference ldev here, since + * we might come from an failed Attach before ldev was set. */ + if (device->ldev) { + rcu_read_lock(); + eh = rcu_dereference(device->ldev->disk_conf)->on_io_error; + rcu_read_unlock(); + + was_io_error = test_and_clear_bit(WAS_IO_ERROR, &device->flags); + + if (was_io_error && eh == EP_CALL_HELPER) + drbd_khelper(device, "local-io-error"); + + /* Immediately allow completion of all application IO, + * that waits for completion from the local disk, + * if this was a force-detach due to disk_timeout + * or administrator request (drbdsetup detach --force). + * Do NOT abort otherwise. + * Aborting local requests may cause serious problems, + * if requests are completed to upper layers already, + * and then later the already submitted local bio completes. + * This can cause DMA into former bio pages that meanwhile + * have been re-used for other things. + * So aborting local requests may cause crashes, + * or even worse, silent data corruption. + */ + if (test_and_clear_bit(FORCE_DETACH, &device->flags)) + tl_abort_disk_io(device); + + /* current state still has to be D_FAILED, + * there is only one way out: to D_DISKLESS, + * and that may only happen after our put_ldev below. */ + if (device->state.disk != D_FAILED) + drbd_err(device, + "ASSERT FAILED: disk is %s during detach\n", + drbd_disk_str(device->state.disk)); + + if (ns.conn >= C_CONNECTED) + drbd_send_state(peer_device, ns); + + drbd_rs_cancel_all(device); + + /* In case we want to get something to stable storage still, + * this may be the last chance. + * Following put_ldev may transition to D_DISKLESS. */ + drbd_md_sync(device); + } + put_ldev(device); + } + + /* second half of local IO error, failure to attach, + * or administrative detach, + * after local_cnt references have reached zero again */ + if (os.disk != D_DISKLESS && ns.disk == D_DISKLESS) { + /* We must still be diskless, + * re-attach has to be serialized with this! */ + if (device->state.disk != D_DISKLESS) + drbd_err(device, + "ASSERT FAILED: disk is %s while going diskless\n", + drbd_disk_str(device->state.disk)); + + if (ns.conn >= C_CONNECTED) + drbd_send_state(peer_device, ns); + /* corresponding get_ldev in __drbd_set_state + * this may finally trigger drbd_ldev_destroy. */ + put_ldev(device); + } + + /* Notify peer that I had a local IO error, and did not detached.. */ + if (os.disk == D_UP_TO_DATE && ns.disk == D_INCONSISTENT && ns.conn >= C_CONNECTED) + drbd_send_state(peer_device, ns); + + /* Disks got bigger while they were detached */ + if (ns.disk > D_NEGOTIATING && ns.pdsk > D_NEGOTIATING && + test_and_clear_bit(RESYNC_AFTER_NEG, &device->flags)) { + if (ns.conn == C_CONNECTED) + resync_after_online_grow(device); + } + + /* A resync finished or aborted, wake paused devices... */ + if ((os.conn > C_CONNECTED && ns.conn <= C_CONNECTED) || + (os.peer_isp && !ns.peer_isp) || + (os.user_isp && !ns.user_isp)) + resume_next_sg(device); + + /* sync target done with resync. Explicitly notify peer, even though + * it should (at least for non-empty resyncs) already know itself. */ + if (os.disk < D_UP_TO_DATE && os.conn >= C_SYNC_SOURCE && ns.conn == C_CONNECTED) + drbd_send_state(peer_device, ns); + + /* Verify finished, or reached stop sector. Peer did not know about + * the stop sector, and we may even have changed the stop sector during + * verify to interrupt/stop early. Send the new state. */ + if (os.conn == C_VERIFY_S && ns.conn == C_CONNECTED + && verify_can_do_stop_sector(device)) + drbd_send_state(peer_device, ns); + + /* This triggers bitmap writeout of potentially still unwritten pages + * if the resync finished cleanly, or aborted because of peer disk + * failure, or because of connection loss. + * For resync aborted because of local disk failure, we cannot do + * any bitmap writeout anymore. + * No harm done if some bits change during this phase. + */ + if (os.conn > C_CONNECTED && ns.conn <= C_CONNECTED && get_ldev(device)) { + drbd_queue_bitmap_io(device, &drbd_bm_write_copy_pages, NULL, + "write from resync_finished", BM_LOCKED_CHANGE_ALLOWED); + put_ldev(device); + } + + if (ns.disk == D_DISKLESS && + ns.conn == C_STANDALONE && + ns.role == R_SECONDARY) { + if (os.aftr_isp != ns.aftr_isp) + resume_next_sg(device); + } + + drbd_md_sync(device); +} + +struct after_conn_state_chg_work { + struct drbd_work w; + enum drbd_conns oc; + union drbd_state ns_min; + union drbd_state ns_max; /* new, max state, over all devices */ + enum chg_state_flags flags; + struct drbd_connection *connection; +}; + +static int w_after_conn_state_ch(struct drbd_work *w, int unused) +{ + struct after_conn_state_chg_work *acscw = + container_of(w, struct after_conn_state_chg_work, w); + struct drbd_connection *connection = acscw->connection; + enum drbd_conns oc = acscw->oc; + union drbd_state ns_max = acscw->ns_max; + struct drbd_peer_device *peer_device; + int vnr; + + kfree(acscw); + + /* Upon network configuration, we need to start the receiver */ + if (oc == C_STANDALONE && ns_max.conn == C_UNCONNECTED) + drbd_thread_start(&connection->receiver); + + if (oc == C_DISCONNECTING && ns_max.conn == C_STANDALONE) { + struct net_conf *old_conf; + + mutex_lock(&connection->resource->conf_update); + old_conf = connection->net_conf; + connection->my_addr_len = 0; + connection->peer_addr_len = 0; + RCU_INIT_POINTER(connection->net_conf, NULL); + conn_free_crypto(connection); + mutex_unlock(&connection->resource->conf_update); + + synchronize_rcu(); + kfree(old_conf); + } + + if (ns_max.susp_fen) { + /* case1: The outdate peer handler is successful: */ + if (ns_max.pdsk <= D_OUTDATED) { + rcu_read_lock(); + idr_for_each_entry(&connection->peer_devices, peer_device, vnr) { + struct drbd_device *device = peer_device->device; + if (test_bit(NEW_CUR_UUID, &device->flags)) { + drbd_uuid_new_current(device); + clear_bit(NEW_CUR_UUID, &device->flags); + } + } + rcu_read_unlock(); + spin_lock_irq(&connection->resource->req_lock); + _tl_restart(connection, CONNECTION_LOST_WHILE_PENDING); + _conn_request_state(connection, + (union drbd_state) { { .susp_fen = 1 } }, + (union drbd_state) { { .susp_fen = 0 } }, + CS_VERBOSE); + spin_unlock_irq(&connection->resource->req_lock); + } + } + kref_put(&connection->kref, drbd_destroy_connection); + + conn_md_sync(connection); + + return 0; +} + +static void conn_old_common_state(struct drbd_connection *connection, union drbd_state *pcs, enum chg_state_flags *pf) +{ + enum chg_state_flags flags = ~0; + struct drbd_peer_device *peer_device; + int vnr, first_vol = 1; + union drbd_dev_state os, cs = { + { .role = R_SECONDARY, + .peer = R_UNKNOWN, + .conn = connection->cstate, + .disk = D_DISKLESS, + .pdsk = D_UNKNOWN, + } }; + + rcu_read_lock(); + idr_for_each_entry(&connection->peer_devices, peer_device, vnr) { + struct drbd_device *device = peer_device->device; + os = device->state; + + if (first_vol) { + cs = os; + first_vol = 0; + continue; + } + + if (cs.role != os.role) + flags &= ~CS_DC_ROLE; + + if (cs.peer != os.peer) + flags &= ~CS_DC_PEER; + + if (cs.conn != os.conn) + flags &= ~CS_DC_CONN; + + if (cs.disk != os.disk) + flags &= ~CS_DC_DISK; + + if (cs.pdsk != os.pdsk) + flags &= ~CS_DC_PDSK; + } + rcu_read_unlock(); + + *pf |= CS_DC_MASK; + *pf &= flags; + (*pcs).i = cs.i; +} + +static enum drbd_state_rv +conn_is_valid_transition(struct drbd_connection *connection, union drbd_state mask, union drbd_state val, + enum chg_state_flags flags) +{ + enum drbd_state_rv rv = SS_SUCCESS; + union drbd_state ns, os; + struct drbd_peer_device *peer_device; + int vnr; + + rcu_read_lock(); + idr_for_each_entry(&connection->peer_devices, peer_device, vnr) { + struct drbd_device *device = peer_device->device; + os = drbd_read_state(device); + ns = sanitize_state(device, os, apply_mask_val(os, mask, val), NULL); + + if (flags & CS_IGN_OUTD_FAIL && ns.disk == D_OUTDATED && os.disk < D_OUTDATED) + ns.disk = os.disk; + + if (ns.i == os.i) + continue; + + rv = is_valid_transition(os, ns); + + if (rv >= SS_SUCCESS && !(flags & CS_HARD)) { + rv = is_valid_state(device, ns); + if (rv < SS_SUCCESS) { + if (is_valid_state(device, os) == rv) + rv = is_valid_soft_transition(os, ns, connection); + } else + rv = is_valid_soft_transition(os, ns, connection); + } + + if (rv < SS_SUCCESS) { + if (flags & CS_VERBOSE) + print_st_err(device, os, ns, rv); + break; + } + } + rcu_read_unlock(); + + return rv; +} + +static void +conn_set_state(struct drbd_connection *connection, union drbd_state mask, union drbd_state val, + union drbd_state *pns_min, union drbd_state *pns_max, enum chg_state_flags flags) +{ + union drbd_state ns, os, ns_max = { }; + union drbd_state ns_min = { + { .role = R_MASK, + .peer = R_MASK, + .conn = val.conn, + .disk = D_MASK, + .pdsk = D_MASK + } }; + struct drbd_peer_device *peer_device; + enum drbd_state_rv rv; + int vnr, number_of_volumes = 0; + + if (mask.conn == C_MASK) { + /* remember last connect time so request_timer_fn() won't + * kill newly established sessions while we are still trying to thaw + * previously frozen IO */ + if (connection->cstate != C_WF_REPORT_PARAMS && val.conn == C_WF_REPORT_PARAMS) + connection->last_reconnect_jif = jiffies; + + connection->cstate = val.conn; + } + + rcu_read_lock(); + idr_for_each_entry(&connection->peer_devices, peer_device, vnr) { + struct drbd_device *device = peer_device->device; + number_of_volumes++; + os = drbd_read_state(device); + ns = apply_mask_val(os, mask, val); + ns = sanitize_state(device, os, ns, NULL); + + if (flags & CS_IGN_OUTD_FAIL && ns.disk == D_OUTDATED && os.disk < D_OUTDATED) + ns.disk = os.disk; + + rv = __drbd_set_state(device, ns, flags, NULL); + if (rv < SS_SUCCESS) + BUG(); + + ns.i = device->state.i; + ns_max.role = max_role(ns.role, ns_max.role); + ns_max.peer = max_role(ns.peer, ns_max.peer); + ns_max.conn = max_t(enum drbd_conns, ns.conn, ns_max.conn); + ns_max.disk = max_t(enum drbd_disk_state, ns.disk, ns_max.disk); + ns_max.pdsk = max_t(enum drbd_disk_state, ns.pdsk, ns_max.pdsk); + + ns_min.role = min_role(ns.role, ns_min.role); + ns_min.peer = min_role(ns.peer, ns_min.peer); + ns_min.conn = min_t(enum drbd_conns, ns.conn, ns_min.conn); + ns_min.disk = min_t(enum drbd_disk_state, ns.disk, ns_min.disk); + ns_min.pdsk = min_t(enum drbd_disk_state, ns.pdsk, ns_min.pdsk); + } + rcu_read_unlock(); + + if (number_of_volumes == 0) { + ns_min = ns_max = (union drbd_state) { { + .role = R_SECONDARY, + .peer = R_UNKNOWN, + .conn = val.conn, + .disk = D_DISKLESS, + .pdsk = D_UNKNOWN + } }; + } + + ns_min.susp = ns_max.susp = connection->resource->susp; + ns_min.susp_nod = ns_max.susp_nod = connection->resource->susp_nod; + ns_min.susp_fen = ns_max.susp_fen = connection->resource->susp_fen; + + *pns_min = ns_min; + *pns_max = ns_max; +} + +static enum drbd_state_rv +_conn_rq_cond(struct drbd_connection *connection, union drbd_state mask, union drbd_state val) +{ + enum drbd_state_rv err, rv = SS_UNKNOWN_ERROR; /* continue waiting */; + + if (test_and_clear_bit(CONN_WD_ST_CHG_OKAY, &connection->flags)) + rv = SS_CW_SUCCESS; + + if (test_and_clear_bit(CONN_WD_ST_CHG_FAIL, &connection->flags)) + rv = SS_CW_FAILED_BY_PEER; + + err = conn_is_valid_transition(connection, mask, val, 0); + if (err == SS_SUCCESS && connection->cstate == C_WF_REPORT_PARAMS) + return rv; + + return err; +} + +enum drbd_state_rv +_conn_request_state(struct drbd_connection *connection, union drbd_state mask, union drbd_state val, + enum chg_state_flags flags) +{ + enum drbd_state_rv rv = SS_SUCCESS; + struct after_conn_state_chg_work *acscw; + enum drbd_conns oc = connection->cstate; + union drbd_state ns_max, ns_min, os; + bool have_mutex = false; + + if (mask.conn) { + rv = is_valid_conn_transition(oc, val.conn); + if (rv < SS_SUCCESS) + goto abort; + } + + rv = conn_is_valid_transition(connection, mask, val, flags); + if (rv < SS_SUCCESS) + goto abort; + + if (oc == C_WF_REPORT_PARAMS && val.conn == C_DISCONNECTING && + !(flags & (CS_LOCAL_ONLY | CS_HARD))) { + + /* This will be a cluster-wide state change. + * Need to give up the spinlock, grab the mutex, + * then send the state change request, ... */ + spin_unlock_irq(&connection->resource->req_lock); + mutex_lock(&connection->cstate_mutex); + have_mutex = true; + + set_bit(CONN_WD_ST_CHG_REQ, &connection->flags); + if (conn_send_state_req(connection, mask, val)) { + /* sending failed. */ + clear_bit(CONN_WD_ST_CHG_REQ, &connection->flags); + rv = SS_CW_FAILED_BY_PEER; + /* need to re-aquire the spin lock, though */ + goto abort_unlocked; + } + + if (val.conn == C_DISCONNECTING) + set_bit(DISCONNECT_SENT, &connection->flags); + + /* ... and re-aquire the spinlock. + * If _conn_rq_cond() returned >= SS_SUCCESS, we must call + * conn_set_state() within the same spinlock. */ + spin_lock_irq(&connection->resource->req_lock); + wait_event_lock_irq(connection->ping_wait, + (rv = _conn_rq_cond(connection, mask, val)), + connection->resource->req_lock); + clear_bit(CONN_WD_ST_CHG_REQ, &connection->flags); + if (rv < SS_SUCCESS) + goto abort; + } + + conn_old_common_state(connection, &os, &flags); + flags |= CS_DC_SUSP; + conn_set_state(connection, mask, val, &ns_min, &ns_max, flags); + conn_pr_state_change(connection, os, ns_max, flags); + + acscw = kmalloc(sizeof(*acscw), GFP_ATOMIC); + if (acscw) { + acscw->oc = os.conn; + acscw->ns_min = ns_min; + acscw->ns_max = ns_max; + acscw->flags = flags; + acscw->w.cb = w_after_conn_state_ch; + kref_get(&connection->kref); + acscw->connection = connection; + drbd_queue_work(&connection->sender_work, &acscw->w); + } else { + drbd_err(connection, "Could not kmalloc an acscw\n"); + } + + abort: + if (have_mutex) { + /* mutex_unlock() "... must not be used in interrupt context.", + * so give up the spinlock, then re-aquire it */ + spin_unlock_irq(&connection->resource->req_lock); + abort_unlocked: + mutex_unlock(&connection->cstate_mutex); + spin_lock_irq(&connection->resource->req_lock); + } + if (rv < SS_SUCCESS && flags & CS_VERBOSE) { + drbd_err(connection, "State change failed: %s\n", drbd_set_st_err_str(rv)); + drbd_err(connection, " mask = 0x%x val = 0x%x\n", mask.i, val.i); + drbd_err(connection, " old_conn:%s wanted_conn:%s\n", drbd_conn_str(oc), drbd_conn_str(val.conn)); + } + return rv; +} + +enum drbd_state_rv +conn_request_state(struct drbd_connection *connection, union drbd_state mask, union drbd_state val, + enum chg_state_flags flags) +{ + enum drbd_state_rv rv; + + spin_lock_irq(&connection->resource->req_lock); + rv = _conn_request_state(connection, mask, val, flags); + spin_unlock_irq(&connection->resource->req_lock); + + return rv; +} |