/* drbd.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 . Copyright (C) 2002-2008, Lars Ellenberg . 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. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define __KERNEL_SYSCALLS__ #include #include #include #include "drbd_int.h" #include "drbd_protocol.h" #include "drbd_req.h" /* only for _req_mod in tl_release and tl_clear */ #include "drbd_vli.h" #include "drbd_debugfs.h" static DEFINE_MUTEX(drbd_main_mutex); static int drbd_open(struct block_device *bdev, fmode_t mode); static void drbd_release(struct gendisk *gd, fmode_t mode); static void md_sync_timer_fn(unsigned long data); static int w_bitmap_io(struct drbd_work *w, int unused); MODULE_AUTHOR("Philipp Reisner , " "Lars Ellenberg "); MODULE_DESCRIPTION("drbd - Distributed Replicated Block Device v" REL_VERSION); MODULE_VERSION(REL_VERSION); MODULE_LICENSE("GPL"); MODULE_PARM_DESC(minor_count, "Approximate number of drbd devices (" __stringify(DRBD_MINOR_COUNT_MIN) "-" __stringify(DRBD_MINOR_COUNT_MAX) ")"); MODULE_ALIAS_BLOCKDEV_MAJOR(DRBD_MAJOR); #include /* allow_open_on_secondary */ MODULE_PARM_DESC(allow_oos, "DONT USE!"); /* thanks to these macros, if compiled into the kernel (not-module), * this becomes the boot parameter drbd.minor_count */ module_param(minor_count, uint, 0444); module_param(disable_sendpage, bool, 0644); module_param(allow_oos, bool, 0); module_param(proc_details, int, 0644); #ifdef CONFIG_DRBD_FAULT_INJECTION int enable_faults; int fault_rate; static int fault_count; int fault_devs; /* bitmap of enabled faults */ module_param(enable_faults, int, 0664); /* fault rate % value - applies to all enabled faults */ module_param(fault_rate, int, 0664); /* count of faults inserted */ module_param(fault_count, int, 0664); /* bitmap of devices to insert faults on */ module_param(fault_devs, int, 0644); #endif /* module parameter, defined */ unsigned int minor_count = DRBD_MINOR_COUNT_DEF; bool disable_sendpage; bool allow_oos; int proc_details; /* Detail level in proc drbd*/ /* Module parameter for setting the user mode helper program * to run. Default is /sbin/drbdadm */ char usermode_helper[80] = "/sbin/drbdadm"; module_param_string(usermode_helper, usermode_helper, sizeof(usermode_helper), 0644); /* in 2.6.x, our device mapping and config info contains our virtual gendisks * as member "struct gendisk *vdisk;" */ struct idr drbd_devices; struct list_head drbd_resources; struct kmem_cache *drbd_request_cache; struct kmem_cache *drbd_ee_cache; /* peer requests */ struct kmem_cache *drbd_bm_ext_cache; /* bitmap extents */ struct kmem_cache *drbd_al_ext_cache; /* activity log extents */ mempool_t *drbd_request_mempool; mempool_t *drbd_ee_mempool; mempool_t *drbd_md_io_page_pool; struct bio_set *drbd_md_io_bio_set; /* I do not use a standard mempool, because: 1) I want to hand out the pre-allocated objects first. 2) I want to be able to interrupt sleeping allocation with a signal. Note: This is a single linked list, the next pointer is the private member of struct page. */ struct page *drbd_pp_pool; spinlock_t drbd_pp_lock; int drbd_pp_vacant; wait_queue_head_t drbd_pp_wait; DEFINE_RATELIMIT_STATE(drbd_ratelimit_state, 5 * HZ, 5); static const struct block_device_operations drbd_ops = { .owner = THIS_MODULE, .open = drbd_open, .release = drbd_release, }; struct bio *bio_alloc_drbd(gfp_t gfp_mask) { struct bio *bio; if (!drbd_md_io_bio_set) return bio_alloc(gfp_mask, 1); bio = bio_alloc_bioset(gfp_mask, 1, drbd_md_io_bio_set); if (!bio) return NULL; return bio; } #ifdef __CHECKER__ /* When checking with sparse, and this is an inline function, sparse will give tons of false positives. When this is a real functions sparse works. */ int _get_ldev_if_state(struct drbd_device *device, enum drbd_disk_state mins) { int io_allowed; atomic_inc(&device->local_cnt); io_allowed = (device->state.disk >= mins); if (!io_allowed) { if (atomic_dec_and_test(&device->local_cnt)) wake_up(&device->misc_wait); } return io_allowed; } #endif /** * tl_release() - mark as BARRIER_ACKED all requests in the corresponding transfer log epoch * @connection: DRBD connection. * @barrier_nr: Expected identifier of the DRBD write barrier packet. * @set_size: Expected number of requests before that barrier. * * In case the passed barrier_nr or set_size does not match the oldest * epoch of not yet barrier-acked requests, this function will cause a * termination of the connection. */ void tl_release(struct drbd_connection *connection, unsigned int barrier_nr, unsigned int set_size) { struct drbd_request *r; struct drbd_request *req = NULL; int expect_epoch = 0; int expect_size = 0; spin_lock_irq(&connection->resource->req_lock); /* find oldest not yet barrier-acked write request, * count writes in its epoch. */ list_for_each_entry(r, &connection->transfer_log, tl_requests) { const unsigned s = r->rq_state; if (!req) { if (!(s & RQ_WRITE)) continue; if (!(s & RQ_NET_MASK)) continue; if (s & RQ_NET_DONE) continue; req = r; expect_epoch = req->epoch; expect_size ++; } else { if (r->epoch != expect_epoch) break; if (!(s & RQ_WRITE)) continue; /* if (s & RQ_DONE): not expected */ /* if (!(s & RQ_NET_MASK)): not expected */ expect_size++; } } /* first some paranoia code */ if (req == NULL) { drbd_err(connection, "BAD! BarrierAck #%u received, but no epoch in tl!?\n", barrier_nr); goto bail; } if (expect_epoch != barrier_nr) { drbd_err(connection, "BAD! BarrierAck #%u received, expected #%u!\n", barrier_nr, expect_epoch); goto bail; } if (expect_size != set_size) { drbd_err(connection, "BAD! BarrierAck #%u received with n_writes=%u, expected n_writes=%u!\n", barrier_nr, set_size, expect_size); goto bail; } /* Clean up list of requests processed during current epoch. */ /* this extra list walk restart is paranoia, * to catch requests being barrier-acked "unexpectedly". * It usually should find the same req again, or some READ preceding it. */ list_for_each_entry(req, &connection->transfer_log, tl_requests) if (req->epoch == expect_epoch) break; list_for_each_entry_safe_from(req, r, &connection->transfer_log, tl_requests) { if (req->epoch != expect_epoch) break; _req_mod(req, BARRIER_ACKED); } spin_unlock_irq(&connection->resource->req_lock); return; bail: spin_unlock_irq(&connection->resource->req_lock); conn_request_state(connection, NS(conn, C_PROTOCOL_ERROR), CS_HARD); } /** * _tl_restart() - Walks the transfer log, and applies an action to all requests * @connection: DRBD connection to operate on. * @what: The action/event to perform with all request objects * * @what might be one of CONNECTION_LOST_WHILE_PENDING, RESEND, FAIL_FROZEN_DISK_IO, * RESTART_FROZEN_DISK_IO. */ /* must hold resource->req_lock */ void _tl_restart(struct drbd_connection *connection, enum drbd_req_event what) { struct drbd_request *req, *r; list_for_each_entry_safe(req, r, &connection->transfer_log, tl_requests) _req_mod(req, what); } void tl_restart(struct drbd_connection *connection, enum drbd_req_event what) { spin_lock_irq(&connection->resource->req_lock); _tl_restart(connection, what); spin_unlock_irq(&connection->resource->req_lock); } /** * tl_clear() - Clears all requests and &struct drbd_tl_epoch objects out of the TL * @device: DRBD device. * * This is called after the connection to the peer was lost. The storage covered * by the requests on the transfer gets marked as our of sync. Called from the * receiver thread and the worker thread. */ void tl_clear(struct drbd_connection *connection) { tl_restart(connection, CONNECTION_LOST_WHILE_PENDING); } /** * tl_abort_disk_io() - Abort disk I/O for all requests for a certain device in the TL * @device: DRBD device. */ void tl_abort_disk_io(struct drbd_device *device) { struct drbd_connection *connection = first_peer_device(device)->connection; struct drbd_request *req, *r; spin_lock_irq(&connection->resource->req_lock); list_for_each_entry_safe(req, r, &connection->transfer_log, tl_requests) { if (!(req->rq_state & RQ_LOCAL_PENDING)) continue; if (req->device != device) continue; _req_mod(req, ABORT_DISK_IO); } spin_unlock_irq(&connection->resource->req_lock); } static int drbd_thread_setup(void *arg) { struct drbd_thread *thi = (struct drbd_thread *) arg; struct drbd_resource *resource = thi->resource; unsigned long flags; int retval; snprintf(current->comm, sizeof(current->comm), "drbd_%c_%s", thi->name[0], resource->name); restart: retval = thi->function(thi); spin_lock_irqsave(&thi->t_lock, flags); /* if the receiver has been "EXITING", the last thing it did * was set the conn state to "StandAlone", * if now a re-connect request comes in, conn state goes C_UNCONNECTED, * and receiver thread will be "started". * drbd_thread_start needs to set "RESTARTING" in that case. * t_state check and assignment needs to be within the same spinlock, * so either thread_start sees EXITING, and can remap to RESTARTING, * or thread_start see NONE, and can proceed as normal. */ if (thi->t_state == RESTARTING) { drbd_info(resource, "Restarting %s thread\n", thi->name); thi->t_state = RUNNING; spin_unlock_irqrestore(&thi->t_lock, flags); goto restart; } thi->task = NULL; thi->t_state = NONE; smp_mb(); complete_all(&thi->stop); spin_unlock_irqrestore(&thi->t_lock, flags); drbd_info(resource, "Terminating %s\n", current->comm); /* Release mod reference taken when thread was started */ if (thi->connection) kref_put(&thi->connection->kref, drbd_destroy_connection); kref_put(&resource->kref, drbd_destroy_resource); module_put(THIS_MODULE); return retval; } static void drbd_thread_init(struct drbd_resource *resource, struct drbd_thread *thi, int (*func) (struct drbd_thread *), const char *name) { spin_lock_init(&thi->t_lock); thi->task = NULL; thi->t_state = NONE; thi->function = func; thi->resource = resource; thi->connection = NULL; thi->name = name; } int drbd_thread_start(struct drbd_thread *thi) { struct drbd_resource *resource = thi->resource; struct task_struct *nt; unsigned long flags; /* is used from state engine doing drbd_thread_stop_nowait, * while holding the req lock irqsave */ spin_lock_irqsave(&thi->t_lock, flags); switch (thi->t_state) { case NONE: drbd_info(resource, "Starting %s thread (from %s [%d])\n", thi->name, current->comm, current->pid); /* Get ref on module for thread - this is released when thread exits */ if (!try_module_get(THIS_MODULE)) { drbd_err(resource, "Failed to get module reference in drbd_thread_start\n"); spin_unlock_irqrestore(&thi->t_lock, flags); return false; } kref_get(&resource->kref); if (thi->connection) kref_get(&thi->connection->kref); init_completion(&thi->stop); thi->reset_cpu_mask = 1; thi->t_state = RUNNING; spin_unlock_irqrestore(&thi->t_lock, flags); flush_signals(current); /* otherw. may get -ERESTARTNOINTR */ nt = kthread_create(drbd_thread_setup, (void *) thi, "drbd_%c_%s", thi->name[0], thi->resource->name); if (IS_ERR(nt)) { drbd_err(resource, "Couldn't start thread\n"); if (thi->connection) kref_put(&thi->connection->kref, drbd_destroy_connection); kref_put(&resource->kref, drbd_destroy_resource); module_put(THIS_MODULE); return false; } spin_lock_irqsave(&thi->t_lock, flags); thi->task = nt; thi->t_state = RUNNING; spin_unlock_irqrestore(&thi->t_lock, flags); wake_up_process(nt); break; case EXITING: thi->t_state = RESTARTING; drbd_info(resource, "Restarting %s thread (from %s [%d])\n", thi->name, current->comm, current->pid); /* fall through */ case RUNNING: case RESTARTING: default: spin_unlock_irqrestore(&thi->t_lock, flags); break; } return true; } void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait) { unsigned long flags; enum drbd_thread_state ns = restart ? RESTARTING : EXITING; /* may be called from state engine, holding the req lock irqsave */ spin_lock_irqsave(&thi->t_lock, flags); if (thi->t_state == NONE) { spin_unlock_irqrestore(&thi->t_lock, flags); if (restart) drbd_thread_start(thi); return; } if (thi->t_state != ns) { if (thi->task == NULL) { spin_unlock_irqrestore(&thi->t_lock, flags); return; } thi->t_state = ns; smp_mb(); init_completion(&thi->stop); if (thi->task != current) force_sig(DRBD_SIGKILL, thi->task); } spin_unlock_irqrestore(&thi->t_lock, flags); if (wait) wait_for_completion(&thi->stop); } int conn_lowest_minor(struct drbd_connection *connection) { struct drbd_peer_device *peer_device; int vnr = 0, minor = -1; rcu_read_lock(); peer_device = idr_get_next(&connection->peer_devices, &vnr); if (peer_device) minor = device_to_minor(peer_device->device); rcu_read_unlock(); return minor; } #ifdef CONFIG_SMP /** * drbd_calc_cpu_mask() - Generate CPU masks, spread over all CPUs * * Forces all threads of a resource onto the same CPU. This is beneficial for * DRBD's performance. May be overwritten by user's configuration. */ static void drbd_calc_cpu_mask(cpumask_var_t *cpu_mask) { unsigned int *resources_per_cpu, min_index = ~0; resources_per_cpu = kzalloc(nr_cpu_ids * sizeof(*resources_per_cpu), GFP_KERNEL); if (resources_per_cpu) { struct drbd_resource *resource; unsigned int cpu, min = ~0; rcu_read_lock(); for_each_resource_rcu(resource, &drbd_resources) { for_each_cpu(cpu, resource->cpu_mask) resources_per_cpu[cpu]++; } rcu_read_unlock(); for_each_online_cpu(cpu) { if (resources_per_cpu[cpu] < min) { min = resources_per_cpu[cpu]; min_index = cpu; } } kfree(resources_per_cpu); } if (min_index == ~0) { cpumask_setall(*cpu_mask); return; } cpumask_set_cpu(min_index, *cpu_mask); } /** * drbd_thread_current_set_cpu() - modifies the cpu mask of the _current_ thread * @device: DRBD device. * @thi: drbd_thread object * * call in the "main loop" of _all_ threads, no need for any mutex, current won't die * prematurely. */ void drbd_thread_current_set_cpu(struct drbd_thread *thi) { struct drbd_resource *resource = thi->resource; struct task_struct *p = current; if (!thi->reset_cpu_mask) return; thi->reset_cpu_mask = 0; set_cpus_allowed_ptr(p, resource->cpu_mask); } #else #define drbd_calc_cpu_mask(A) ({}) #endif /** * drbd_header_size - size of a packet header * * The header size is a multiple of 8, so any payload following the header is * word aligned on 64-bit architectures. (The bitmap send and receive code * relies on this.) */ unsigned int drbd_header_size(struct drbd_connection *connection) { if (connection->agreed_pro_version >= 100) { BUILD_BUG_ON(!IS_ALIGNED(sizeof(struct p_header100), 8)); return sizeof(struct p_header100); } else { BUILD_BUG_ON(sizeof(struct p_header80) != sizeof(struct p_header95)); BUILD_BUG_ON(!IS_ALIGNED(sizeof(struct p_header80), 8)); return sizeof(struct p_header80); } } static unsigned int prepare_header80(struct p_header80 *h, enum drbd_packet cmd, int size) { h->magic = cpu_to_be32(DRBD_MAGIC); h->command = cpu_to_be16(cmd); h->length = cpu_to_be16(size); return sizeof(struct p_header80); } static unsigned int prepare_header95(struct p_header95 *h, enum drbd_packet cmd, int size) { h->magic = cpu_to_be16(DRBD_MAGIC_BIG); h->command = cpu_to_be16(cmd); h->length = cpu_to_be32(size); return sizeof(struct p_header95); } static unsigned int prepare_header100(struct p_header100 *h, enum drbd_packet cmd, int size, int vnr) { h->magic = cpu_to_be32(DRBD_MAGIC_100); h->volume = cpu_to_be16(vnr); h->command = cpu_to_be16(cmd); h->length = cpu_to_be32(size); h->pad = 0; return sizeof(struct p_header100); } static unsigned int prepare_header(struct drbd_connection *connection, int vnr, void *buffer, enum drbd_packet cmd, int size) { if (connection->agreed_pro_version >= 100) return prepare_header100(buffer, cmd, size, vnr); else if (connection->agreed_pro_version >= 95 && size > DRBD_MAX_SIZE_H80_PACKET) return prepare_header95(buffer, cmd, size); else return prepare_header80(buffer, cmd, size); } static void *__conn_prepare_command(struct drbd_connection *connection, struct drbd_socket *sock) { if (!sock->socket) return NULL; return sock->sbuf + drbd_header_size(connection); } void *conn_prepare_command(struct drbd_connection *connection, struct drbd_socket *sock) { void *p; mutex_lock(&sock->mutex); p = __conn_prepare_command(connection, sock); if (!p) mutex_unlock(&sock->mutex); return p; } void *drbd_prepare_command(struct drbd_peer_device *peer_device, struct drbd_socket *sock) { return conn_prepare_command(peer_device->connection, sock); } static int __send_command(struct drbd_connection *connection, int vnr, struct drbd_socket *sock, enum drbd_packet cmd, unsigned int header_size, void *data, unsigned int size) { int msg_flags; int err; /* * Called with @data == NULL and the size of the data blocks in @size * for commands that send data blocks. For those commands, omit the * MSG_MORE flag: this will increase the likelihood that data blocks * which are page aligned on the sender will end up page aligned on the * receiver. */ msg_flags = data ? MSG_MORE : 0; header_size += prepare_header(connection, vnr, sock->sbuf, cmd, header_size + size); err = drbd_send_all(connection, sock->socket, sock->sbuf, header_size, msg_flags); if (data && !err) err = drbd_send_all(connection, sock->socket, data, size, 0); /* DRBD protocol "pings" are latency critical. * This is supposed to trigger tcp_push_pending_frames() */ if (!err && (cmd == P_PING || cmd == P_PING_ACK)) drbd_tcp_nodelay(sock->socket); return err; } static int __conn_send_command(struct drbd_connection *connection, struct drbd_socket *sock, enum drbd_packet cmd, unsigned int header_size, void *data, unsigned int size) { return __send_command(connection, 0, sock, cmd, header_size, data, size); } int conn_send_command(struct drbd_connection *connection, struct drbd_socket *sock, enum drbd_packet cmd, unsigned int header_size, void *data, unsigned int size) { int err; err = __conn_send_command(connection, sock, cmd, header_size, data, size); mutex_unlock(&sock->mutex); return err; } int drbd_send_command(struct drbd_peer_device *peer_device, struct drbd_socket *sock, enum drbd_packet cmd, unsigned int header_size, void *data, unsigned int size) { int err; err = __send_command(peer_device->connection, peer_device->device->vnr, sock, cmd, header_size, data, size); mutex_unlock(&sock->mutex); return err; } int drbd_send_ping(struct drbd_connection *connection) { struct drbd_socket *sock; sock = &connection->meta; if (!conn_prepare_command(connection, sock)) return -EIO; return conn_send_command(connection, sock, P_PING, 0, NULL, 0); } int drbd_send_ping_ack(struct drbd_connection *connection) { struct drbd_socket *sock; sock = &connection->meta; if (!conn_prepare_command(connection, sock)) return -EIO; return conn_send_command(connection, sock, P_PING_ACK, 0, NULL, 0); } int drbd_send_sync_param(struct drbd_peer_device *peer_device) { struct drbd_socket *sock; struct p_rs_param_95 *p; int size; const int apv = peer_device->connection->agreed_pro_version; enum drbd_packet cmd; struct net_conf *nc; struct disk_conf *dc; sock = &peer_device->connection->data; p = drbd_prepare_command(peer_device, sock); if (!p) return -EIO; rcu_read_lock(); nc = rcu_dereference(peer_device->connection->net_conf); size = apv <= 87 ? sizeof(struct p_rs_param) : apv == 88 ? sizeof(struct p_rs_param) + strlen(nc->verify_alg) + 1 : apv <= 94 ? sizeof(struct p_rs_param_89) : /* apv >= 95 */ sizeof(struct p_rs_param_95); cmd = apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM; /* initialize verify_alg and csums_alg */ memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX); if (get_ldev(peer_device->device)) { dc = rcu_dereference(peer_device->device->ldev->disk_conf); p->resync_rate = cpu_to_be32(dc->resync_rate); p->c_plan_ahead = cpu_to_be32(dc->c_plan_ahead); p->c_delay_target = cpu_to_be32(dc->c_delay_target); p->c_fill_target = cpu_to_be32(dc->c_fill_target); p->c_max_rate = cpu_to_be32(dc->c_max_rate); put_ldev(peer_device->device); } else { p->resync_rate = cpu_to_be32(DRBD_RESYNC_RATE_DEF); p->c_plan_ahead = cpu_to_be32(DRBD_C_PLAN_AHEAD_DEF); p->c_delay_target = cpu_to_be32(DRBD_C_DELAY_TARGET_DEF); p->c_fill_target = cpu_to_be32(DRBD_C_FILL_TARGET_DEF); p->c_max_rate = cpu_to_be32(DRBD_C_MAX_RATE_DEF); } if (apv >= 88) strcpy(p->verify_alg, nc->verify_alg); if (apv >= 89) strcpy(p->csums_alg, nc->csums_alg); rcu_read_unlock(); return drbd_send_command(peer_device, sock, cmd, size, NULL, 0); } int __drbd_send_protocol(struct drbd_connection *connection, enum drbd_packet cmd) { struct drbd_socket *sock; struct p_protocol *p; struct net_conf *nc; int size, cf; sock = &connection->data; p = __conn_prepare_command(connection, sock); if (!p) return -EIO; rcu_read_lock(); nc = rcu_dereference(connection->net_conf); if (nc->tentative && connection->agreed_pro_version < 92) { rcu_read_unlock(); mutex_unlock(&sock->mutex); drbd_err(connection, "--dry-run is not supported by peer"); return -EOPNOTSUPP; } size = sizeof(*p); if (connection->agreed_pro_version >= 87) size += strlen(nc->integrity_alg) + 1; p->protocol = cpu_to_be32(nc->wire_protocol); p->after_sb_0p = cpu_to_be32(nc->after_sb_0p); p->after_sb_1p = cpu_to_be32(nc->after_sb_1p); p->after_sb_2p = cpu_to_be32(nc->after_sb_2p); p->two_primaries = cpu_to_be32(nc->two_primaries); cf = 0; if (nc->discard_my_data) cf |= CF_DISCARD_MY_DATA; if (nc->tentative) cf |= CF_DRY_RUN; p->conn_flags = cpu_to_be32(cf); if (connection->agreed_pro_version >= 87) strcpy(p->integrity_alg, nc->integrity_alg); rcu_read_unlock(); return __conn_send_command(connection, sock, cmd, size, NULL, 0); } int drbd_send_protocol(struct drbd_connection *connection) { int err; mutex_lock(&connection->data.mutex); err = __drbd_send_protocol(connection, P_PROTOCOL); mutex_unlock(&connection->data.mutex); return err; } static int _drbd_send_uuids(struct drbd_peer_device *peer_device, u64 uuid_flags) { struct drbd_device *device = peer_device->device; struct drbd_socket *sock; struct p_uuids *p; int i; if (!get_ldev_if_state(device, D_NEGOTIATING)) return 0; sock = &peer_device->connection->data; p = drbd_prepare_command(peer_device, sock); if (!p) { put_ldev(device); return -EIO; } spin_lock_irq(&device->ldev->md.uuid_lock); for (i = UI_CURRENT; i < UI_SIZE; i++) p->uuid[i] = cpu_to_be64(device->ldev->md.uuid[i]); spin_unlock_irq(&device->ldev->md.uuid_lock); device->comm_bm_set = drbd_bm_total_weight(device); p->uuid[UI_SIZE] = cpu_to_be64(device->comm_bm_set); rcu_read_lock(); uuid_flags |= rcu_dereference(peer_device->connection->net_conf)->discard_my_data ? 1 : 0; rcu_read_unlock(); uuid_flags |= test_bit(CRASHED_PRIMARY, &device->flags) ? 2 : 0; uuid_flags |= device->new_state_tmp.disk == D_INCONSISTENT ? 4 : 0; p->uuid[UI_FLAGS] = cpu_to_be64(uuid_flags); put_ldev(device); return drbd_send_command(peer_device, sock, P_UUIDS, sizeof(*p), NULL, 0); } int drbd_send_uuids(struct drbd_peer_device *peer_device) { return _drbd_send_uuids(peer_device, 0); } int drbd_send_uuids_skip_initial_sync(struct drbd_peer_device *peer_device) { return _drbd_send_uuids(peer_device, 8); } void drbd_print_uuids(struct drbd_device *device, const char *text) { if (get_ldev_if_state(device, D_NEGOTIATING)) { u64 *uuid = device->ldev->md.uuid; drbd_info(device, "%s %016llX:%016llX:%016llX:%016llX\n", text, (unsigned long long)uuid[UI_CURRENT], (unsigned long long)uuid[UI_BITMAP], (unsigned long long)uuid[UI_HISTORY_START], (unsigned long long)uuid[UI_HISTORY_END]); put_ldev(device); } else { drbd_info(device, "%s effective data uuid: %016llX\n", text, (unsigned long long)device->ed_uuid); } } void drbd_gen_and_send_sync_uuid(struct drbd_peer_device *peer_device) { struct drbd_device *device = peer_device->device; struct drbd_socket *sock; struct p_rs_uuid *p; u64 uuid; D_ASSERT(device, device->state.disk == D_UP_TO_DATE); uuid = device->ldev->md.uuid[UI_BITMAP]; if (uuid && uuid != UUID_JUST_CREATED) uuid = uuid + UUID_NEW_BM_OFFSET; else get_random_bytes(&uuid, sizeof(u64)); drbd_uuid_set(device, UI_BITMAP, uuid); drbd_print_uuids(device, "updated sync UUID"); drbd_md_sync(device); sock = &peer_device->connection->data; p = drbd_prepare_command(peer_device, sock); if (p) { p->uuid = cpu_to_be64(uuid); drbd_send_command(peer_device, sock, P_SYNC_UUID, sizeof(*p), NULL, 0); } } int drbd_send_sizes(struct drbd_peer_device *peer_device, int trigger_reply, enum dds_flags flags) { struct drbd_device *device = peer_device->device; struct drbd_socket *sock; struct p_sizes *p; sector_t d_size, u_size; int q_order_type; unsigned int max_bio_size; if (get_ldev_if_state(device, D_NEGOTIATING)) { D_ASSERT(device, device->ldev->backing_bdev); d_size = drbd_get_max_capacity(device->ldev); rcu_read_lock(); u_size = rcu_dereference(device->ldev->disk_conf)->disk_size; rcu_read_unlock(); q_order_type = drbd_queue_order_type(device); max_bio_size = queue_max_hw_sectors(device->ldev->backing_bdev->bd_disk->queue) << 9; max_bio_size = min(max_bio_size, DRBD_MAX_BIO_SIZE); put_ldev(device); } else { d_size = 0; u_size = 0; q_order_type = QUEUE_ORDERED_NONE; max_bio_size = DRBD_MAX_BIO_SIZE; /* ... multiple BIOs per peer_request */ } sock = &peer_device->connection->data; p = drbd_prepare_command(peer_device, sock); if (!p) return -EIO; if (peer_device->connection->agreed_pro_version <= 94) max_bio_size = min(max_bio_size, DRBD_MAX_SIZE_H80_PACKET); else if (peer_device->connection->agreed_pro_version < 100) max_bio_size = min(max_bio_size, DRBD_MAX_BIO_SIZE_P95); p->d_size = cpu_to_be64(d_size); p->u_size = cpu_to_be64(u_size); p->c_size = cpu_to_be64(trigger_reply ? 0 : drbd_get_capacity(device->this_bdev)); p->max_bio_size = cpu_to_be32(max_bio_size); p->queue_order_type = cpu_to_be16(q_order_type); p->dds_flags = cpu_to_be16(flags); return drbd_send_command(peer_device, sock, P_SIZES, sizeof(*p), NULL, 0); } /** * drbd_send_current_state() - Sends the drbd state to the peer * @peer_device: DRBD peer device. */ int drbd_send_current_state(struct drbd_peer_device *peer_device) { struct drbd_socket *sock; struct p_state *p; sock = &peer_device->connection->data; p = drbd_prepare_command(peer_device, sock); if (!p) return -EIO; p->state = cpu_to_be32(peer_device->device->state.i); /* Within the send mutex */ return drbd_send_command(peer_device, sock, P_STATE, sizeof(*p), NULL, 0); } /** * drbd_send_state() - After a state change, sends the new state to the peer * @peer_device: DRBD peer device. * @state: the state to send, not necessarily the current state. * * Each state change queues an "after_state_ch" work, which will eventually * send the resulting new state to the peer. If more state changes happen * between queuing and processing of the after_state_ch work, we still * want to send each intermediary state in the order it occurred. */ int drbd_send_state(struct drbd_peer_device *peer_device, union drbd_state state) { struct drbd_socket *sock; struct p_state *p; sock = &peer_device->connection->data; p = drbd_prepare_command(peer_device, sock); if (!p) return -EIO; p->state = cpu_to_be32(state.i); /* Within the send mutex */ return drbd_send_command(peer_device, sock, P_STATE, sizeof(*p), NULL, 0); } int drbd_send_state_req(struct drbd_peer_device *peer_device, union drbd_state mask, union drbd_state val) { struct drbd_socket *sock; struct p_req_state *p; sock = &peer_device->connection->data; p = drbd_prepare_command(peer_device, sock); if (!p) return -EIO; p->mask = cpu_to_be32(mask.i); p->val = cpu_to_be32(val.i); return drbd_send_command(peer_device, sock, P_STATE_CHG_REQ, sizeof(*p), NULL, 0); } int conn_send_state_req(struct drbd_connection *connection, union drbd_state mask, union drbd_state val) { enum drbd_packet cmd; struct drbd_socket *sock; struct p_req_state *p; cmd = connection->agreed_pro_version < 100 ? P_STATE_CHG_REQ : P_CONN_ST_CHG_REQ; sock = &connection->data; p = conn_prepare_command(connection, sock); if (!p) return -EIO; p->mask = cpu_to_be32(mask.i); p->val = cpu_to_be32(val.i); return conn_send_command(connection, sock, cmd, sizeof(*p), NULL, 0); } void drbd_send_sr_reply(struct drbd_peer_device *peer_device, enum drbd_state_rv retcode) { struct drbd_socket *sock; struct p_req_state_reply *p; sock = &peer_device->connection->meta; p = drbd_prepare_command(peer_device, sock); if (p) { p->retcode = cpu_to_be32(retcode); drbd_send_command(peer_device, sock, P_STATE_CHG_REPLY, sizeof(*p), NULL, 0); } } void conn_send_sr_reply(struct drbd_connection *connection, enum drbd_state_rv retcode) { struct drbd_socket *sock; struct p_req_state_reply *p; enum drbd_packet cmd = connection->agreed_pro_version < 100 ? P_STATE_CHG_REPLY : P_CONN_ST_CHG_REPLY; sock = &connection->meta; p = conn_prepare_command(connection, sock); if (p) { p->retcode = cpu_to_be32(retcode); conn_send_command(connection, sock, cmd, sizeof(*p), NULL, 0); } } static void dcbp_set_code(struct p_compressed_bm *p, enum drbd_bitmap_code code) { BUG_ON(code & ~0xf); p->encoding = (p->encoding & ~0xf) | code; } static void dcbp_set_start(struct p_compressed_bm *p, int set) { p->encoding = (p->encoding & ~0x80) | (set ? 0x80 : 0); } static void dcbp_set_pad_bits(struct p_compressed_bm *p, int n) { BUG_ON(n & ~0x7); p->encoding = (p->encoding & (~0x7 << 4)) | (n << 4); } static int fill_bitmap_rle_bits(struct drbd_device *device, struct p_compressed_bm *p, unsigned int size, struct bm_xfer_ctx *c) { struct bitstream bs; unsigned long plain_bits; unsigned long tmp; unsigned long rl; unsigned len; unsigned toggle; int bits, use_rle; /* may we use this feature? */ rcu_read_lock(); use_rle = rcu_dereference(first_peer_device(device)->connection->net_conf)->use_rle; rcu_read_unlock(); if (!use_rle || first_peer_device(device)->connection->agreed_pro_version < 90) return 0; if (c->bit_offset >= c->bm_bits) return 0; /* nothing to do. */ /* use at most thus many bytes */ bitstream_init(&bs, p->code, size, 0); memset(p->code, 0, size); /* plain bits covered in this code string */ plain_bits = 0; /* p->encoding & 0x80 stores whether the first run length is set. * bit offset is implicit. * start with toggle == 2 to be able to tell the first iteration */ toggle = 2; /* see how much plain bits we can stuff into one packet * using RLE and VLI. */ do { tmp = (toggle == 0) ? _drbd_bm_find_next_zero(device, c->bit_offset) : _drbd_bm_find_next(device, c->bit_offset); if (tmp == -1UL) tmp = c->bm_bits; rl = tmp - c->bit_offset; if (toggle == 2) { /* first iteration */ if (rl == 0) { /* the first checked bit was set, * store start value, */ dcbp_set_start(p, 1); /* but skip encoding of zero run length */ toggle = !toggle; continue; } dcbp_set_start(p, 0); } /* paranoia: catch zero runlength. * can only happen if bitmap is modified while we scan it. */ if (rl == 0) { drbd_err(device, "unexpected zero runlength while encoding bitmap " "t:%u bo:%lu\n", toggle, c->bit_offset); return -1; } bits = vli_encode_bits(&bs, rl); if (bits == -ENOBUFS) /* buffer full */ break; if (bits <= 0) { drbd_err(device, "error while encoding bitmap: %d\n", bits); return 0; } toggle = !toggle; plain_bits += rl; c->bit_offset = tmp; } while (c->bit_offset < c->bm_bits); len = bs.cur.b - p->code + !!bs.cur.bit; if (plain_bits < (len << 3)) { /* incompressible with this method. * we need to rewind both word and bit position. */ c->bit_offset -= plain_bits; bm_xfer_ctx_bit_to_word_offset(c); c->bit_offset = c->word_offset * BITS_PER_LONG; return 0; } /* RLE + VLI was able to compress it just fine. * update c->word_offset. */ bm_xfer_ctx_bit_to_word_offset(c); /* store pad_bits */ dcbp_set_pad_bits(p, (8 - bs.cur.bit) & 0x7); return len; } /** * send_bitmap_rle_or_plain * * Return 0 when done, 1 when another iteration is needed, and a negative error * code upon failure. */ static int send_bitmap_rle_or_plain(struct drbd_device *device, struct bm_xfer_ctx *c) { struct drbd_socket *sock = &first_peer_device(device)->connection->data; unsigned int header_size = drbd_header_size(first_peer_device(device)->connection); struct p_compressed_bm *p = sock->sbuf + header_size; int len, err; len = fill_bitmap_rle_bits(device, p, DRBD_SOCKET_BUFFER_SIZE - header_size - sizeof(*p), c); if (len < 0) return -EIO; if (len) { dcbp_set_code(p, RLE_VLI_Bits); err = __send_command(first_peer_device(device)->connection, device->vnr, sock, P_COMPRESSED_BITMAP, sizeof(*p) + len, NULL, 0); c->packets[0]++; c->bytes[0] += header_size + sizeof(*p) + len; if (c->bit_offset >= c->bm_bits) len = 0; /* DONE */ } else { /* was not compressible. * send a buffer full of plain text bits instead. */ unsigned int data_size; unsigned long num_words; unsigned long *p = sock->sbuf + header_size; data_size = DRBD_SOCKET_BUFFER_SIZE - header_size; num_words = min_t(size_t, data_size / sizeof(*p), c->bm_words - c->word_offset); len = num_words * sizeof(*p); if (len) drbd_bm_get_lel(device, c->word_offset, num_words, p); err = __send_command(first_peer_device(device)->connection, device->vnr, sock, P_BITMAP, len, NULL, 0); c->word_offset += num_words; c->bit_offset = c->word_offset * BITS_PER_LONG; c->packets[1]++; c->bytes[1] += header_size + len; if (c->bit_offset > c->bm_bits) c->bit_offset = c->bm_bits; } if (!err) { if (len == 0) { INFO_bm_xfer_stats(device, "send", c); return 0; } else return 1; } return -EIO; } /* See the comment at receive_bitmap() */ static int _drbd_send_bitmap(struct drbd_device *device) { struct bm_xfer_ctx c; int err; if (!expect(device->bitmap)) return false; if (get_ldev(device)) { if (drbd_md_test_flag(device->ldev, MDF_FULL_SYNC)) { drbd_info(device, "Writing the whole bitmap, MDF_FullSync was set.\n"); drbd_bm_set_all(device); if (drbd_bm_write(device)) { /* write_bm did fail! Leave full sync flag set in Meta P_DATA * but otherwise process as per normal - need to tell other * side that a full resync is required! */ drbd_err(device, "Failed to write bitmap to disk!\n"); } else { drbd_md_clear_flag(device, MDF_FULL_SYNC); drbd_md_sync(device); } } put_ldev(device); } c = (struct bm_xfer_ctx) { .bm_bits = drbd_bm_bits(device), .bm_words = drbd_bm_words(device), }; do { err = send_bitmap_rle_or_plain(device, &c); } while (err > 0); return err == 0; } int drbd_send_bitmap(struct drbd_device *device) { struct drbd_socket *sock = &first_peer_device(device)->connection->data; int err = -1; mutex_lock(&sock->mutex); if (sock->socket) err = !_drbd_send_bitmap(device); mutex_unlock(&sock->mutex); return err; } void drbd_send_b_ack(struct drbd_connection *connection, u32 barrier_nr, u32 set_size) { struct drbd_socket *sock; struct p_barrier_ack *p; if (connection->cstate < C_WF_REPORT_PARAMS) return; sock = &connection->meta; p = conn_prepare_command(connection, sock); if (!p) return; p->barrier = barrier_nr; p->set_size = cpu_to_be32(set_size); conn_send_command(connection, sock, P_BARRIER_ACK, sizeof(*p), NULL, 0); } /** * _drbd_send_ack() - Sends an ack packet * @device: DRBD device. * @cmd: Packet command code. * @sector: sector, needs to be in big endian byte order * @blksize: size in byte, needs to be in big endian byte order * @block_id: Id, big endian byte order */ static int _drbd_send_ack(struct drbd_peer_device *peer_device, enum drbd_packet cmd, u64 sector, u32 blksize, u64 block_id) { struct drbd_socket *sock; struct p_block_ack *p; if (peer_device->device->state.conn < C_CONNECTED) return -EIO; sock = &peer_device->connection->meta; p = drbd_prepare_command(peer_device, sock); if (!p) return -EIO; p->sector = sector; p->block_id = block_id; p->blksize = blksize; p->seq_num = cpu_to_be32(atomic_inc_return(&peer_device->device->packet_seq)); return drbd_send_command(peer_device, sock, cmd, sizeof(*p), NULL, 0); } /* dp->sector and dp->block_id already/still in network byte order, * data_size is payload size according to dp->head, * and may need to be corrected for digest size. */ void drbd_send_ack_dp(struct drbd_peer_device *peer_device, enum drbd_packet cmd, struct p_data *dp, int data_size) { if (peer_device->connection->peer_integrity_tfm) data_size -= crypto_hash_digestsize(peer_device->connection->peer_integrity_tfm); _drbd_send_ack(peer_device, cmd, dp->sector, cpu_to_be32(data_size), dp->block_id); } void drbd_send_ack_rp(struct drbd_peer_device *peer_device, enum drbd_packet cmd, struct p_block_req *rp) { _drbd_send_ack(peer_device, cmd, rp->sector, rp->blksize, rp->block_id); } /** * drbd_send_ack() - Sends an ack packet * @device: DRBD device * @cmd: packet command code * @peer_req: peer request */ int drbd_send_ack(struct drbd_peer_device *peer_device, enum drbd_packet cmd, struct drbd_peer_request *peer_req) { return _drbd_send_ack(peer_device, cmd, cpu_to_be64(peer_req->i.sector), cpu_to_be32(peer_req->i.size), peer_req->block_id); } /* This function misuses the block_id field to signal if the blocks * are is sync or not. */ int drbd_send_ack_ex(struct drbd_peer_device *peer_device, enum drbd_packet cmd, sector_t sector, int blksize, u64 block_id) { return _drbd_send_ack(peer_device, cmd, cpu_to_be64(sector), cpu_to_be32(blksize), cpu_to_be64(block_id)); } int drbd_send_drequest(struct drbd_peer_device *peer_device, int cmd, sector_t sector, int size, u64 block_id) { struct drbd_socket *sock; struct p_block_req *p; sock = &peer_device->connection->data; p = drbd_prepare_command(peer_device, sock); if (!p) return -EIO; p->sector = cpu_to_be64(sector); p->block_id = block_id; p->blksize = cpu_to_be32(size); return drbd_send_command(peer_device, sock, cmd, sizeof(*p), NULL, 0); } int drbd_send_drequest_csum(struct drbd_peer_device *peer_device, sector_t sector, int size, void *digest, int digest_size, enum drbd_packet cmd) { struct drbd_socket *sock; struct p_block_req *p; /* FIXME: Put the digest into the preallocated socket buffer. */ sock = &peer_device->connection->data; p = drbd_prepare_command(peer_device, sock); if (!p) return -EIO; p->sector = cpu_to_be64(sector); p->block_id = ID_SYNCER /* unused */; p->blksize = cpu_to_be32(size); return drbd_send_command(peer_device, sock, cmd, sizeof(*p), digest, digest_size); } int drbd_send_ov_request(struct drbd_peer_device *peer_device, sector_t sector, int size) { struct drbd_socket *sock; struct p_block_req *p; sock = &peer_device->connection->data; p = drbd_prepare_command(peer_device, sock); if (!p) return -EIO; p->sector = cpu_to_be64(sector); p->block_id = ID_SYNCER /* unused */; p->blksize = cpu_to_be32(size); return drbd_send_command(peer_device, sock, P_OV_REQUEST, sizeof(*p), NULL, 0); } /* called on sndtimeo * returns false if we should retry, * true if we think connection is dead */ static int we_should_drop_the_connection(struct drbd_connection *connection, struct socket *sock) { int drop_it; /* long elapsed = (long)(jiffies - device->last_received); */ drop_it = connection->meta.socket == sock || !connection->asender.task || get_t_state(&connection->asender) != RUNNING || connection->cstate < C_WF_REPORT_PARAMS; if (drop_it) return true; drop_it = !--connection->ko_count; if (!drop_it) { drbd_err(connection, "[%s/%d] sock_sendmsg time expired, ko = %u\n", current->comm, current->pid, connection->ko_count); request_ping(connection); } return drop_it; /* && (device->state == R_PRIMARY) */; } static void drbd_update_congested(struct drbd_connection *connection) { struct sock *sk = connection->data.socket->sk; if (sk->sk_wmem_queued > sk->sk_sndbuf * 4 / 5) set_bit(NET_CONGESTED, &connection->flags); } /* The idea of sendpage seems to be to put some kind of reference * to the page into the skb, and to hand it over to the NIC. In * this process get_page() gets called. * * As soon as the page was really sent over the network put_page() * gets called by some part of the network layer. [ NIC driver? ] * * [ get_page() / put_page() increment/decrement the count. If count * reaches 0 the page will be freed. ] * * This works nicely with pages from FSs. * But this means that in protocol A we might signal IO completion too early! * * In order not to corrupt data during a resync we must make sure * that we do not reuse our own buffer pages (EEs) to early, therefore * we have the net_ee list. * * XFS seems to have problems, still, it submits pages with page_count == 0! * As a workaround, we disable sendpage on pages * with page_count == 0 or PageSlab. */ static int _drbd_no_send_page(struct drbd_peer_device *peer_device, struct page *page, int offset, size_t size, unsigned msg_flags) { struct socket *socket; void *addr; int err; socket = peer_device->connection->data.socket; addr = kmap(page) + offset; err = drbd_send_all(peer_device->connection, socket, addr, size, msg_flags); kunmap(page); if (!err) peer_device->device->send_cnt += size >> 9; return err; } static int _drbd_send_page(struct drbd_peer_device *peer_device, struct page *page, int offset, size_t size, unsigned msg_flags) { struct socket *socket = peer_device->connection->data.socket; mm_segment_t oldfs = get_fs(); int len = size; int err = -EIO; /* e.g. XFS meta- & log-data is in slab pages, which have a * page_count of 0 and/or have PageSlab() set. * we cannot use send_page for those, as that does get_page(); * put_page(); and would cause either a VM_BUG directly, or * __page_cache_release a page that would actually still be referenced * by someone, leading to some obscure delayed Oops somewhere else. */ if (disable_sendpage || (page_count(page) < 1) || PageSlab(page)) return _drbd_no_send_page(peer_device, page, offset, size, msg_flags); msg_flags |= MSG_NOSIGNAL; drbd_update_congested(peer_device->connection); set_fs(KERNEL_DS); do { int sent; sent = socket->ops->sendpage(socket, page, offset, len, msg_flags); if (sent <= 0) { if (sent == -EAGAIN) { if (we_should_drop_the_connection(peer_device->connection, socket)) break; continue; } drbd_warn(peer_device->device, "%s: size=%d len=%d sent=%d\n", __func__, (int)size, len, sent); if (sent < 0) err = sent; break; } len -= sent; offset += sent; } while (len > 0 /* THINK && device->cstate >= C_CONNECTED*/); set_fs(oldfs); clear_bit(NET_CONGESTED, &peer_device->connection->flags); if (len == 0) { err = 0; peer_device->device->send_cnt += size >> 9; } return err; } static int _drbd_send_bio(struct drbd_peer_device *peer_device, struct bio *bio) { struct bio_vec bvec; struct bvec_iter iter; /* hint all but last page with MSG_MORE */ bio_for_each_segment(bvec, bio, iter) { int err; err = _drbd_no_send_page(peer_device, bvec.bv_page, bvec.bv_offset, bvec.bv_len, bio_iter_last(bvec, iter) ? 0 : MSG_MORE); if (err) return err; } return 0; } static int _drbd_send_zc_bio(struct drbd_peer_device *peer_device, struct bio *bio) { struct bio_vec bvec; struct bvec_iter iter; /* hint all but last page with MSG_MORE */ bio_for_each_segment(bvec, bio, iter) { int err; err = _drbd_send_page(peer_device, bvec.bv_page, bvec.bv_offset, bvec.bv_len, bio_iter_last(bvec, iter) ? 0 : MSG_MORE); if (err) return err; } return 0; } static int _drbd_send_zc_ee(struct drbd_peer_device *peer_device, struct drbd_peer_request *peer_req) { struct page *page = peer_req->pages; unsigned len = peer_req->i.size; int err; /* hint all but last page with MSG_MORE */ page_chain_for_each(page) { unsigned l = min_t(unsigned, len, PAGE_SIZE); err = _drbd_send_page(peer_device, page, 0, l, page_chain_next(page) ? MSG_MORE : 0); if (err) return err; len -= l; } return 0; } static u32 bio_flags_to_wire(struct drbd_connection *connection, unsigned long bi_rw) { if (connection->agreed_pro_version >= 95) return (bi_rw & REQ_SYNC ? DP_RW_SYNC : 0) | (bi_rw & REQ_FUA ? DP_FUA : 0) | (bi_rw & REQ_FLUSH ? DP_FLUSH : 0) | (bi_rw & REQ_DISCARD ? DP_DISCARD : 0); else return bi_rw & REQ_SYNC ? DP_RW_SYNC : 0; } /* Used to send write or TRIM aka REQ_DISCARD requests * R_PRIMARY -> Peer (P_DATA, P_TRIM) */ int drbd_send_dblock(struct drbd_peer_device *peer_device, struct drbd_request *req) { struct drbd_device *device = peer_device->device; struct drbd_socket *sock; struct p_data *p; unsigned int dp_flags = 0; int digest_size; int err; sock = &peer_device->connection->data; p = drbd_prepare_command(peer_device, sock); digest_size = peer_device->connection->integrity_tfm ? crypto_hash_digestsize(peer_device->connection->integrity_tfm) : 0; if (!p) return -EIO; p->sector = cpu_to_be64(req->i.sector); p->block_id = (unsigned long)req; p->seq_num = cpu_to_be32(atomic_inc_return(&device->packet_seq)); dp_flags = bio_flags_to_wire(peer_device->connection, req->master_bio->bi_rw); if (device->state.conn >= C_SYNC_SOURCE && device->state.conn <= C_PAUSED_SYNC_T) dp_flags |= DP_MAY_SET_IN_SYNC; if (peer_device->connection->agreed_pro_version >= 100) { if (req->rq_state & RQ_EXP_RECEIVE_ACK) dp_flags |= DP_SEND_RECEIVE_ACK; /* During resync, request an explicit write ack, * even in protocol != C */ if (req->rq_state & RQ_EXP_WRITE_ACK || (dp_flags & DP_MAY_SET_IN_SYNC)) dp_flags |= DP_SEND_WRITE_ACK; } p->dp_flags = cpu_to_be32(dp_flags); if (dp_flags & DP_DISCARD) { struct p_trim *t = (struct p_trim*)p; t->size = cpu_to_be32(req->i.size); err = __send_command(peer_device->connection, device->vnr, sock, P_TRIM, sizeof(*t), NULL, 0); goto out; } /* our digest is still only over the payload. * TRIM does not carry any payload. */ if (digest_size) drbd_csum_bio(peer_device->connection->integrity_tfm, req->master_bio, p + 1); err = __send_command(peer_device->connection, device->vnr, sock, P_DATA, sizeof(*p) + digest_size, NULL, req->i.size); if (!err) { /* For protocol A, we have to memcpy the payload into * socket buffers, as we may complete right away * as soon as we handed it over to tcp, at which point the data * pages may become invalid. * * For data-integrity enabled, we copy it as well, so we can be * sure that even if the bio pages may still be modified, it * won't change the data on the wire, thus if the digest checks * out ok after sending on this side, but does not fit on the * receiving side, we sure have detected corruption elsewhere. */ if (!(req->rq_state & (RQ_EXP_RECEIVE_ACK | RQ_EXP_WRITE_ACK)) || digest_size) err = _drbd_send_bio(peer_device, req->master_bio); else err = _drbd_send_zc_bio(peer_device, req->master_bio); /* double check digest, sometimes buffers have been modified in flight. */ if (digest_size > 0 && digest_size <= 64) { /* 64 byte, 512 bit, is the largest digest size * currently supported in kernel crypto. */ unsigned char digest[64]; drbd_csum_bio(peer_device->connection->integrity_tfm, req->master_bio, digest); if (memcmp(p + 1, digest, digest_size)) { drbd_warn(device, "Digest mismatch, buffer modified by upper layers during write: %llus +%u\n", (unsigned long long)req->i.sector, req->i.size); } } /* else if (digest_size > 64) { ... Be noisy about digest too large ... } */ } out: mutex_unlock(&sock->mutex); /* locked by drbd_prepare_command() */ return err; } /* answer packet, used to send data back for read requests: * Peer -> (diskless) R_PRIMARY (P_DATA_REPLY) * C_SYNC_SOURCE -> C_SYNC_TARGET (P_RS_DATA_REPLY) */ int drbd_send_block(struct drbd_peer_device *peer_device, enum drbd_packet cmd, struct drbd_peer_request *peer_req) { struct drbd_device *device = peer_device->device; struct drbd_socket *sock; struct p_data *p; int err; int digest_size; sock = &peer_device->connection->data; p = drbd_prepare_command(peer_device, sock); digest_size = peer_device->connection->integrity_tfm ? crypto_hash_digestsize(peer_device->connection->integrity_tfm) : 0; if (!p) return -EIO; p->sector = cpu_to_be64(peer_req->i.sector); p->block_id = peer_req->block_id; p->seq_num = 0; /* unused */ p->dp_flags = 0; if (digest_size) drbd_csum_ee(peer_device->connection->integrity_tfm, peer_req, p + 1); err = __send_command(peer_device->connection, device->vnr, sock, cmd, sizeof(*p) + digest_size, NULL, peer_req->i.size); if (!err) err = _drbd_send_zc_ee(peer_device, peer_req); mutex_unlock(&sock->mutex); /* locked by drbd_prepare_command() */ return err; } int drbd_send_out_of_sync(struct drbd_peer_device *peer_device, struct drbd_request *req) { struct drbd_socket *sock; struct p_block_desc *p; sock = &peer_device->connection->data; p = drbd_prepare_command(peer_device, sock); if (!p) return -EIO; p->sector = cpu_to_be64(req->i.sector); p->blksize = cpu_to_be32(req->i.size); return drbd_send_command(peer_device, sock, P_OUT_OF_SYNC, sizeof(*p), NULL, 0); } /* drbd_send distinguishes two cases: Packets sent via the data socket "sock" and packets sent via the meta data socket "msock" sock msock -----------------+-------------------------+------------------------------ timeout conf.timeout / 2 conf.timeout / 2 timeout action send a ping via msock Abort communication and close all sockets */ /* * you must have down()ed the appropriate [m]sock_mutex elsewhere! */ int drbd_send(struct drbd_connection *connection, struct socket *sock, void *buf, size_t size, unsigned msg_flags) { struct kvec iov; struct msghdr msg; int rv, sent = 0; if (!sock) return -EBADR; /* THINK if (signal_pending) return ... ? */ iov.iov_base = buf; iov.iov_len = size; msg.msg_name = NULL; msg.msg_namelen = 0; msg.msg_control = NULL; msg.msg_controllen = 0; msg.msg_flags = msg_flags | MSG_NOSIGNAL; if (sock == connection->data.socket) { rcu_read_lock(); connection->ko_count = rcu_dereference(connection->net_conf)->ko_count; rcu_read_unlock(); drbd_update_congested(connection); } do { /* STRANGE * tcp_sendmsg does _not_ use its size parameter at all ? * * -EAGAIN on timeout, -EINTR on signal. */ /* THINK * do we need to block DRBD_SIG if sock == &meta.socket ?? * otherwise wake_asender() might interrupt some send_*Ack ! */ rv = kernel_sendmsg(sock, &msg, &iov, 1, size); if (rv == -EAGAIN) { if (we_should_drop_the_connection(connection, sock)) break; else continue; } if (rv == -EINTR) { flush_signals(current); rv = 0; } if (rv < 0) break; sent += rv; iov.iov_base += rv; iov.iov_len -= rv; } while (sent < size); if (sock == connection->data.socket) clear_bit(NET_CONGESTED, &connection->flags); if (rv <= 0) { if (rv != -EAGAIN) { drbd_err(connection, "%s_sendmsg returned %d\n", sock == connection->meta.socket ? "msock" : "sock", rv); conn_request_state(connection, NS(conn, C_BROKEN_PIPE), CS_HARD); } else conn_request_state(connection, NS(conn, C_TIMEOUT), CS_HARD); } return sent; } /** * drbd_send_all - Send an entire buffer * * Returns 0 upon success and a negative error value otherwise. */ int drbd_send_all(struct drbd_connection *connection, struct socket *sock, void *buffer, size_t size, unsigned msg_flags) { int err; err = drbd_send(connection, sock, buffer, size, msg_flags); if (err < 0) return err; if (err != size) return -EIO; return 0; } static int drbd_open(struct block_device *bdev, fmode_t mode) { struct drbd_device *device = bdev->bd_disk->private_data; unsigned long flags; int rv = 0; mutex_lock(&drbd_main_mutex); spin_lock_irqsave(&device->resource->req_lock, flags); /* to have a stable device->state.role * and no race with updating open_cnt */ if (device->state.role != R_PRIMARY) { if (mode & FMODE_WRITE) rv = -EROFS; else if (!allow_oos) rv = -EMEDIUMTYPE; } if (!rv) device->open_cnt++; spin_unlock_irqrestore(&device->resource->req_lock, flags); mutex_unlock(&drbd_main_mutex); return rv; } static void drbd_release(struct gendisk *gd, fmode_t mode) { struct drbd_device *device = gd->private_data; mutex_lock(&drbd_main_mutex); device->open_cnt--; mutex_unlock(&drbd_main_mutex); } static void drbd_set_defaults(struct drbd_device *device) { /* Beware! The actual layout differs * between big endian and little endian */ device->state = (union drbd_dev_state) { { .role = R_SECONDARY, .peer = R_UNKNOWN, .conn = C_STANDALONE, .disk = D_DISKLESS, .pdsk = D_UNKNOWN, } }; } void drbd_init_set_defaults(struct drbd_device *device) { /* the memset(,0,) did most of this. * note: only assignments, no allocation in here */ drbd_set_defaults(device); atomic_set(&device->ap_bio_cnt, 0); atomic_set(&device->ap_actlog_cnt, 0); atomic_set(&device->ap_pending_cnt, 0); atomic_set(&device->rs_pending_cnt, 0); atomic_set(&device->unacked_cnt, 0); atomic_set(&device->local_cnt, 0); atomic_set(&device->pp_in_use_by_net, 0); atomic_set(&device->rs_sect_in, 0); atomic_set(&device->rs_sect_ev, 0); atomic_set(&device->ap_in_flight, 0); atomic_set(&device->md_io.in_use, 0); mutex_init(&device->own_state_mutex); device->state_mutex = &device->own_state_mutex; spin_lock_init(&device->al_lock); spin_lock_init(&device->peer_seq_lock); INIT_LIST_HEAD(&device->active_ee); INIT_LIST_HEAD(&device->sync_ee); INIT_LIST_HEAD(&device->done_ee); INIT_LIST_HEAD(&device->read_ee); INIT_LIST_HEAD(&device->net_ee); INIT_LIST_HEAD(&device->resync_reads); INIT_LIST_HEAD(&device->resync_work.list); INIT_LIST_HEAD(&device->unplug_work.list); INIT_LIST_HEAD(&device->bm_io_work.w.list); INIT_LIST_HEAD(&device->pending_master_completion[0]); INIT_LIST_HEAD(&device->pending_master_completion[1]); INIT_LIST_HEAD(&device->pending_completion[0]); INIT_LIST_HEAD(&device->pending_completion[1]); device->resync_work.cb = w_resync_timer; device->unplug_work.cb = w_send_write_hint; device->bm_io_work.w.cb = w_bitmap_io; init_timer(&device->resync_timer); init_timer(&device->md_sync_timer); init_timer(&device->start_resync_timer); init_timer(&device->request_timer); device->resync_timer.function = resync_timer_fn; device->resync_timer.data = (unsigned long) device; device->md_sync_timer.function = md_sync_timer_fn; device->md_sync_timer.data = (unsigned long) device; device->start_resync_timer.function = start_resync_timer_fn; device->start_resync_timer.data = (unsigned long) device; device->request_timer.function = request_timer_fn; device->request_timer.data = (unsigned long) device; init_waitqueue_head(&device->misc_wait); init_waitqueue_head(&device->state_wait); init_waitqueue_head(&device->ee_wait); init_waitqueue_head(&device->al_wait); init_waitqueue_head(&device->seq_wait); device->resync_wenr = LC_FREE; device->peer_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE; device->local_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE; } void drbd_device_cleanup(struct drbd_device *device) { int i; if (first_peer_device(device)->connection->receiver.t_state != NONE) drbd_err(device, "ASSERT FAILED: receiver t_state == %d expected 0.\n", first_peer_device(device)->connection->receiver.t_state); device->al_writ_cnt = device->bm_writ_cnt = device->read_cnt = device->recv_cnt = device->send_cnt = device->writ_cnt = device->p_size = device->rs_start = device->rs_total = device->rs_failed = 0; device->rs_last_events = 0; device->rs_last_sect_ev = 0; for (i = 0; i < DRBD_SYNC_MARKS; i++) { device->rs_mark_left[i] = 0; device->rs_mark_time[i] = 0; } D_ASSERT(device, first_peer_device(device)->connection->net_conf == NULL); drbd_set_my_capacity(device, 0); if (device->bitmap) { /* maybe never allocated. */ drbd_bm_resize(device, 0, 1); drbd_bm_cleanup(device); } drbd_free_ldev(device->ldev); device->ldev = NULL; clear_bit(AL_SUSPENDED, &device->flags); D_ASSERT(device, list_empty(&device->active_ee)); D_ASSERT(device, list_empty(&device->sync_ee)); D_ASSERT(device, list_empty(&device->done_ee)); D_ASSERT(device, list_empty(&device->read_ee)); D_ASSERT(device, list_empty(&device->net_ee)); D_ASSERT(device, list_empty(&device->resync_reads)); D_ASSERT(device, list_empty(&first_peer_device(device)->connection->sender_work.q)); D_ASSERT(device, list_empty(&device->resync_work.list)); D_ASSERT(device, list_empty(&device->unplug_work.list)); drbd_set_defaults(device); } static void drbd_destroy_mempools(void) { struct page *page; while (drbd_pp_pool) { page = drbd_pp_pool; drbd_pp_pool = (struct page *)page_private(page); __free_page(page); drbd_pp_vacant--; } /* D_ASSERT(device, atomic_read(&drbd_pp_vacant)==0); */ if (drbd_md_io_bio_set) bioset_free(drbd_md_io_bio_set); if (drbd_md_io_page_pool) mempool_destroy(drbd_md_io_page_pool); if (drbd_ee_mempool) mempool_destroy(drbd_ee_mempool); if (drbd_request_mempool) mempool_destroy(drbd_request_mempool); if (drbd_ee_cache) kmem_cache_destroy(drbd_ee_cache); if (drbd_request_cache) kmem_cache_destroy(drbd_request_cache); if (drbd_bm_ext_cache) kmem_cache_destroy(drbd_bm_ext_cache); if (drbd_al_ext_cache) kmem_cache_destroy(drbd_al_ext_cache); drbd_md_io_bio_set = NULL; drbd_md_io_page_pool = NULL; drbd_ee_mempool = NULL; drbd_request_mempool = NULL; drbd_ee_cache = NULL; drbd_request_cache = NULL; drbd_bm_ext_cache = NULL; drbd_al_ext_cache = NULL; return; } static int drbd_create_mempools(void) { struct page *page; const int number = (DRBD_MAX_BIO_SIZE/PAGE_SIZE) * minor_count; int i; /* prepare our caches and mempools */ drbd_request_mempool = NULL; drbd_ee_cache = NULL; drbd_request_cache = NULL; drbd_bm_ext_cache = NULL; drbd_al_ext_cache = NULL; drbd_pp_pool = NULL; drbd_md_io_page_pool = NULL; drbd_md_io_bio_set = NULL; /* caches */ drbd_request_cache = kmem_cache_create( "drbd_req", sizeof(struct drbd_request), 0, 0, NULL); if (drbd_request_cache == NULL) goto Enomem; drbd_ee_cache = kmem_cache_create( "drbd_ee", sizeof(struct drbd_peer_request), 0, 0, NULL); if (drbd_ee_cache == NULL) goto Enomem; drbd_bm_ext_cache = kmem_cache_create( "drbd_bm", sizeof(struct bm_extent), 0, 0, NULL); if (drbd_bm_ext_cache == NULL) goto Enomem; drbd_al_ext_cache = kmem_cache_create( "drbd_al", sizeof(struct lc_element), 0, 0, NULL); if (drbd_al_ext_cache == NULL) goto Enomem; /* mempools */ drbd_md_io_bio_set = bioset_create(DRBD_MIN_POOL_PAGES, 0); if (drbd_md_io_bio_set == NULL) goto Enomem; drbd_md_io_page_pool = mempool_create_page_pool(DRBD_MIN_POOL_PAGES, 0); if (drbd_md_io_page_pool == NULL) goto Enomem; drbd_request_mempool = mempool_create(number, mempool_alloc_slab, mempool_free_slab, drbd_request_cache); if (drbd_request_mempool == NULL) goto Enomem; drbd_ee_mempool = mempool_create(number, mempool_alloc_slab, mempool_free_slab, drbd_ee_cache); if (drbd_ee_mempool == NULL) goto Enomem; /* drbd's page pool */ spin_lock_init(&drbd_pp_lock); for (i = 0; i < number; i++) { page = alloc_page(GFP_HIGHUSER); if (!page) goto Enomem; set_page_private(page, (unsigned long)drbd_pp_pool); drbd_pp_pool = page; } drbd_pp_vacant = number; return 0; Enomem: drbd_destroy_mempools(); /* in case we allocated some */ return -ENOMEM; } static void drbd_release_all_peer_reqs(struct drbd_device *device) { int rr; rr = drbd_free_peer_reqs(device, &device->active_ee); if (rr) drbd_err(device, "%d EEs in active list found!\n", rr); rr = drbd_free_peer_reqs(device, &device->sync_ee); if (rr) drbd_err(device, "%d EEs in sync list found!\n", rr); rr = drbd_free_peer_reqs(device, &device->read_ee); if (rr) drbd_err(device, "%d EEs in read list found!\n", rr); rr = drbd_free_peer_reqs(device, &device->done_ee); if (rr) drbd_err(device, "%d EEs in done list found!\n", rr); rr = drbd_free_peer_reqs(device, &device->net_ee); if (rr) drbd_err(device, "%d EEs in net list found!\n", rr); } /* caution. no locking. */ void drbd_destroy_device(struct kref *kref) { struct drbd_device *device = container_of(kref, struct drbd_device, kref); struct drbd_resource *resource = device->resource; struct drbd_peer_device *peer_device, *tmp_peer_device; del_timer_sync(&device->request_timer); /* paranoia asserts */ D_ASSERT(device, device->open_cnt == 0); /* end paranoia asserts */ /* cleanup stuff that may have been allocated during * device (re-)configuration or state changes */ if (device->this_bdev) bdput(device->this_bdev); drbd_free_ldev(device->ldev); device->ldev = NULL; drbd_release_all_peer_reqs(device); lc_destroy(device->act_log); lc_destroy(device->resync); kfree(device->p_uuid); /* device->p_uuid = NULL; */ if (device->bitmap) /* should no longer be there. */ drbd_bm_cleanup(device); __free_page(device->md_io.page); put_disk(device->vdisk); blk_cleanup_queue(device->rq_queue); kfree(device->rs_plan_s); /* not for_each_connection(connection, resource): * those may have been cleaned up and disassociated already. */ for_each_peer_device_safe(peer_device, tmp_peer_device, device) { kref_put(&peer_device->connection->kref, drbd_destroy_connection); kfree(peer_device); } memset(device, 0xfd, sizeof(*device)); kfree(device); kref_put(&resource->kref, drbd_destroy_resource); } /* One global retry thread, if we need to push back some bio and have it * reinserted through our make request function. */ static struct retry_worker { struct workqueue_struct *wq; struct work_struct worker; spinlock_t lock; struct list_head writes; } retry; static void do_retry(struct work_struct *ws) { struct retry_worker *retry = container_of(ws, struct retry_worker, worker); LIST_HEAD(writes); struct drbd_request *r