diff options
Diffstat (limited to 'drivers/block/drbd/drbd_main.c')
| -rw-r--r-- | drivers/block/drbd/drbd_main.c | 3923 |
1 files changed, 3923 insertions, 0 deletions
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c new file mode 100644 index 000000000..c3e4f9d83 --- /dev/null +++ b/drivers/block/drbd/drbd_main.c @@ -0,0 +1,3923 @@ +/* + 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 <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. + + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/jiffies.h> +#include <linux/drbd.h> +#include <linux/uaccess.h> +#include <asm/types.h> +#include <net/sock.h> +#include <linux/ctype.h> +#include <linux/mutex.h> +#include <linux/fs.h> +#include <linux/file.h> +#include <linux/proc_fs.h> +#include <linux/init.h> +#include <linux/mm.h> +#include <linux/memcontrol.h> +#include <linux/mm_inline.h> +#include <linux/slab.h> +#include <linux/random.h> +#include <linux/reboot.h> +#include <linux/notifier.h> +#include <linux/kthread.h> +#include <linux/workqueue.h> +#define __KERNEL_SYSCALLS__ +#include <linux/unistd.h> +#include <linux/vmalloc.h> +#include <linux/sched/signal.h> + +#include <linux/drbd_limits.h> +#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(struct timer_list *t); +static int w_bitmap_io(struct drbd_work *w, int unused); + +MODULE_AUTHOR("Philipp Reisner <phil@linbit.com>, " + "Lars Ellenberg <lars@linbit.com>"); +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 <linux/moduleparam.h> +/* thanks to these macros, if compiled into the kernel (not-module), + * these become boot parameters (e.g., drbd.minor_count) */ + +#ifdef CONFIG_DRBD_FAULT_INJECTION +int drbd_enable_faults; +int drbd_fault_rate; +static int drbd_fault_count; +static int drbd_fault_devs; +/* bitmap of enabled faults */ +module_param_named(enable_faults, drbd_enable_faults, int, 0664); +/* fault rate % value - applies to all enabled faults */ +module_param_named(fault_rate, drbd_fault_rate, int, 0664); +/* count of faults inserted */ +module_param_named(fault_count, drbd_fault_count, int, 0664); +/* bitmap of devices to insert faults on */ +module_param_named(fault_devs, drbd_fault_devs, int, 0644); +#endif + +/* module parameters we can keep static */ +static bool drbd_allow_oos; /* allow_open_on_secondary */ +static bool drbd_disable_sendpage; +MODULE_PARM_DESC(allow_oos, "DONT USE!"); +module_param_named(allow_oos, drbd_allow_oos, bool, 0); +module_param_named(disable_sendpage, drbd_disable_sendpage, bool, 0644); + +/* module parameters we share */ +int drbd_proc_details; /* Detail level in proc drbd*/ +module_param_named(proc_details, drbd_proc_details, int, 0644); +/* module parameters shared with defaults */ +unsigned int drbd_minor_count = DRBD_MINOR_COUNT_DEF; +/* Module parameter for setting the user mode helper program + * to run. Default is /sbin/drbdadm */ +char drbd_usermode_helper[80] = "/sbin/drbdadm"; +module_param_named(minor_count, drbd_minor_count, uint, 0444); +module_param_string(usermode_helper, drbd_usermode_helper, sizeof(drbd_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 mutex resources_mutex; + +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; +struct bio_set drbd_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 (!bioset_initialized(&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, *tmp = 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) { + tmp = req; + break; + } + req = list_prepare_entry(tmp, &connection->transfer_log, tl_requests); + 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); + + allow_kernel_signal(DRBD_SIGKILL); + allow_kernel_signal(SIGXCPU); +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 = kcalloc(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(); + 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); + } +} + +/* communicated if (agreed_features & DRBD_FF_WSAME) */ +static void +assign_p_sizes_qlim(struct drbd_device *device, struct p_sizes *p, + struct request_queue *q) +{ + if (q) { + p->qlim->physical_block_size = cpu_to_be32(queue_physical_block_size(q)); + p->qlim->logical_block_size = cpu_to_be32(queue_logical_block_size(q)); + p->qlim->alignment_offset = cpu_to_be32(queue_alignment_offset(q)); + p->qlim->io_min = cpu_to_be32(queue_io_min(q)); + p->qlim->io_opt = cpu_to_be32(queue_io_opt(q)); + p->qlim->discard_enabled = blk_queue_discard(q); + p->qlim->write_same_capable = !!q->limits.max_write_same_sectors; + } else { + q = device->rq_queue; + p->qlim->physical_block_size = cpu_to_be32(queue_physical_block_size(q)); + p->qlim->logical_block_size = cpu_to_be32(queue_logical_block_size(q)); + p->qlim->alignment_offset = 0; + p->qlim->io_min = cpu_to_be32(queue_io_min(q)); + p->qlim->io_opt = cpu_to_be32(queue_io_opt(q)); + p->qlim->discard_enabled = 0; + p->qlim->write_same_capable = 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; + unsigned int packet_size; + + sock = &peer_device->connection->data; + p = drbd_prepare_command(peer_device, sock); + if (!p) + return -EIO; + + packet_size = sizeof(*p); + if (peer_device->connection->agreed_features & DRBD_FF_WSAME) + packet_size += sizeof(p->qlim[0]); + + memset(p, 0, packet_size); + if (get_ldev_if_state(device, D_NEGOTIATING)) { + struct request_queue *q = bdev_get_queue(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(q) << 9; + max_bio_size = min(max_bio_size, DRBD_MAX_BIO_SIZE); + assign_p_sizes_qlim(device, p, q); + 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 */ + assign_p_sizes_qlim(device, p, NULL); + } + + 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, packet_size, 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_ahash_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_rs_deallocated(struct drbd_peer_device *peer_device, + struct drbd_peer_request *peer_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(peer_req->i.sector); + p->blksize = cpu_to_be32(peer_req->i.size); + p->pad = 0; + return drbd_send_command(peer_device, sock, P_RS_DEALLOCATED, sizeof(*p), NULL, 0); +} + +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->ack_receiver.task + || get_t_state(&connection->ack_receiver) != 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; + 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 (drbd_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); + 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*/); + 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; + /* REQ_OP_WRITE_SAME has only one segment */ + if (bio_op(bio) == REQ_OP_WRITE_SAME) + break; + } + 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; + /* REQ_OP_WRITE_SAME has only one segment */ + if (bio_op(bio) == REQ_OP_WRITE_SAME) + break; + } + 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, + struct bio *bio) +{ + if (connection->agreed_pro_version >= 95) + return (bio->bi_opf & REQ_SYNC ? DP_RW_SYNC : 0) | + (bio->bi_opf & REQ_FUA ? DP_FUA : 0) | + (bio->bi_opf & REQ_PREFLUSH ? DP_FLUSH : 0) | + (bio_op(bio) == REQ_OP_WRITE_SAME ? DP_WSAME : 0) | + (bio_op(bio) == REQ_OP_DISCARD ? DP_DISCARD : 0) | + (bio_op(bio) == REQ_OP_WRITE_ZEROES ? DP_DISCARD : 0); + else + return bio->bi_opf & 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; + struct p_wsame *wsame = NULL; + void *digest_out; + 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_ahash_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); + 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; + } + if (dp_flags & DP_WSAME) { + /* this will only work if DRBD_FF_WSAME is set AND the + * handshake agreed that all nodes and backend devices are + * WRITE_SAME capable and agree on logical_block_size */ + wsame = (struct p_wsame*)p; + digest_out = wsame + 1; + wsame->size = cpu_to_be32(req->i.size); + } else + digest_out = p + 1; + + /* 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, digest_out); + if (wsame) { + err = + __send_command(peer_device->connection, device->vnr, sock, P_WSAME, + sizeof(*wsame) + digest_size, NULL, + bio_iovec(req->master_bio).bv_len); + } else + 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_ahash_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 = {.iov_base = buf, .iov_len = size}; + struct msghdr msg = {.msg_flags = msg_flags | MSG_NOSIGNAL}; + int rv, sent = 0; + + if (!sock) + return -EBADR; + + /* THINK if (signal_pending) return ... ? */ + + iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, &iov, 1, size); + + 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 { + rv = sock_sendmsg(sock, &msg); + 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; + } 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 (!drbd_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); +} + +/* need to hold resource->req_lock */ +void drbd_queue_unplug(struct drbd_device *device) +{ + if (device->state.pdsk >= D_INCONSISTENT && device->state.conn >= C_CONNECTED) { + D_ASSERT(device, device->state.role == R_PRIMARY); + if (test_and_clear_bit(UNPLUG_REMOTE, &device->flags)) { + drbd_queue_work_if_unqueued( + &first_peer_device(device)->connection->sender_work, + &device->unplug_work); + } + } +} + +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; + + timer_setup(&device->resync_timer, resync_timer_fn, 0); + timer_setup(&device->md_sync_timer, md_sync_timer_fn, 0); + timer_setup(&device->start_resync_timer, start_resync_timer_fn, 0); + timer_setup(&device->request_timer, request_timer_fn, 0); + + 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_backing_dev_free(device, 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); */ + + bioset_exit(&drbd_io_bio_set); + bioset_exit(&drbd_md_io_bio_set); + mempool_exit(&drbd_md_io_page_pool); + mempool_exit(&drbd_ee_mempool); + mempool_exit(&drbd_request_mempool); + kmem_cache_destroy(drbd_ee_cache); + kmem_cache_destroy(drbd_request_cache); + kmem_cache_destroy(drbd_bm_ext_cache); + kmem_cache_destroy(drbd_al_ext_cache); + + 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) * drbd_minor_count; + int i, ret; + + /* 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 */ + ret = bioset_init(&drbd_io_bio_set, BIO_POOL_SIZE, 0, 0); + if (ret) + goto Enomem; + + ret = bioset_init(&drbd_md_io_bio_set, DRBD_MIN_POOL_PAGES, 0, + BIOSET_NEED_BVECS); + if (ret) + goto Enomem; + + ret = mempool_init_page_pool(&drbd_md_io_page_pool, DRBD_MIN_POOL_PAGES, 0); + if (ret) + goto Enomem; + + ret = mempool_init_slab_pool(&drbd_request_mempool, number, + drbd_request_cache); + if (ret) + goto Enomem; + + ret = mempool_init_slab_pool(&drbd_ee_mempool, number, drbd_ee_cache); + if (ret) + 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_backing_dev_free(device, 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 *req, *tmp; + + spin_lock_irq(&retry->lock); + list_splice_init(&retry->writes, &writes); + spin_unlock_irq(&retry->lock); + + list_for_each_entry_safe(req, tmp, &writes, tl_requests) { + struct drbd_device *device = req->device; + struct bio *bio = req->master_bio; + unsigned long start_jif = req->start_jif; + bool expected; + + expected = + expect(atomic_read(&req->completion_ref) == 0) && + expect(req->rq_state & RQ_POSTPONED) && + expect((req->rq_state & RQ_LOCAL_PENDING) == 0 || + (req->rq_state & RQ_LOCAL_ABORTED) != 0); + + if (!expected) + drbd_err(device, "req=%p completion_ref=%d rq_state=%x\n", + req, atomic_read(&req->completion_ref), + req->rq_state); + + /* We still need to put one kref associated with the + * "completion_ref" going zero in the code path that queued it + * here. The request object may still be referenced by a + * frozen local req->private_bio, in case we force-detached. + */ + kref_put(&req->kref, drbd_req_destroy); + + /* A single suspended or otherwise blocking device may stall + * all others as well. Fortunately, this code path is to + * recover from a situation that "should not happen": + * concurrent writes in multi-primary setup. + * In a "normal" lifecycle, this workqueue is supposed to be + * destroyed without ever doing anything. + * If it turns out to be an issue anyways, we can do per + * resource (replication group) or per device (minor) retry + * workqueues instead. + */ + + /* We are not just doing generic_make_request(), + * as we want to keep the start_time information. */ + inc_ap_bio(device); + __drbd_make_request(device, bio, start_jif); + } +} + +/* called via drbd_req_put_completion_ref(), + * holds resource->req_lock */ +void drbd_restart_request(struct drbd_request *req) +{ + unsigned long flags; + spin_lock_irqsave(&retry.lock, flags); + list_move_tail(&req->tl_requests, &retry.writes); + spin_unlock_irqrestore(&retry.lock, flags); + + /* Drop the extra reference that would otherwise + * have been dropped by complete_master_bio. + * do_retry() needs to grab a new one. */ + dec_ap_bio(req->device); + + queue_work(retry.wq, &retry.worker); +} + +void drbd_destroy_resource(struct kref *kref) +{ + struct drbd_resource *resource = + container_of(kref, struct drbd_resource, kref); + + idr_destroy(&resource->devices); + free_cpumask_var(resource->cpu_mask); + kfree(resource->name); + memset(resource, 0xf2, sizeof(*resource)); + kfree(resource); +} + +void drbd_free_resource(struct drbd_resource *resource) +{ + struct drbd_connection *connection, *tmp; + + for_each_connection_safe(connection, tmp, resource) { + list_del(&connection->connections); + drbd_debugfs_connection_cleanup(connection); + kref_put(&connection->kref, drbd_destroy_connection); + } + drbd_debugfs_resource_cleanup(resource); + kref_put(&resource->kref, drbd_destroy_resource); +} + +static void drbd_cleanup(void) +{ + unsigned int i; + struct drbd_device *device; + struct drbd_resource *resource, *tmp; + + /* first remove proc, + * drbdsetup uses it's presence to detect + * whether DRBD is loaded. + * If we would get stuck in proc removal, + * but have netlink already deregistered, + * some drbdsetup commands may wait forever + * for an answer. + */ + if (drbd_proc) + remove_proc_entry("drbd", NULL); + + if (retry.wq) + destroy_workqueue(retry.wq); + + drbd_genl_unregister(); + + idr_for_each_entry(&drbd_devices, device, i) + drbd_delete_device(device); + + /* not _rcu since, no other updater anymore. Genl already unregistered */ + for_each_resource_safe(resource, tmp, &drbd_resources) { + list_del(&resource->resources); + drbd_free_resource(resource); + } + + drbd_debugfs_cleanup(); + + drbd_destroy_mempools(); + unregister_blkdev(DRBD_MAJOR, "drbd"); + + idr_destroy(&drbd_devices); + + pr_info("module cleanup done.\n"); +} + +/** + * drbd_congested() - Callback for the flusher thread + * @congested_data: User data + * @bdi_bits: Bits the BDI flusher thread is currently interested in + * + * Returns 1<<WB_async_congested and/or 1<<WB_sync_congested if we are congested. + */ +static int drbd_congested(void *congested_data, int bdi_bits) +{ + struct drbd_device *device = congested_data; + struct request_queue *q; + char reason = '-'; + int r = 0; + + if (!may_inc_ap_bio(device)) { + /* DRBD has frozen IO */ + r = bdi_bits; + reason = 'd'; + goto out; + } + + if (test_bit(CALLBACK_PENDING, &first_peer_device(device)->connection->flags)) { + r |= (1 << WB_async_congested); + /* Without good local data, we would need to read from remote, + * and that would need the worker thread as well, which is + * currently blocked waiting for that usermode helper to + * finish. + */ + if (!get_ldev_if_state(device, D_UP_TO_DATE)) + r |= (1 << WB_sync_congested); + else + put_ldev(device); + r &= bdi_bits; + reason = 'c'; + goto out; + } + + if (get_ldev(device)) { + q = bdev_get_queue(device->ldev->backing_bdev); + r = bdi_congested(q->backing_dev_info, bdi_bits); + put_ldev(device); + if (r) + reason = 'b'; + } + + if (bdi_bits & (1 << WB_async_congested) && + test_bit(NET_CONGESTED, &first_peer_device(device)->connection->flags)) { + r |= (1 << WB_async_congested); + reason = reason == 'b' ? 'a' : 'n'; + } + +out: + device->congestion_reason = reason; + return r; +} + +static void drbd_init_workqueue(struct drbd_work_queue* wq) +{ + spin_lock_init(&wq->q_lock); + INIT_LIST_HEAD(&wq->q); + init_waitqueue_head(&wq->q_wait); +} + +struct completion_work { + struct drbd_work w; + struct completion done; +}; + +static int w_complete(struct drbd_work *w, int cancel) +{ + struct completion_work *completion_work = + container_of(w, struct completion_work, w); + + complete(&completion_work->done); + return 0; +} + +void drbd_flush_workqueue(struct drbd_work_queue *work_queue) +{ + struct completion_work completion_work; + + completion_work.w.cb = w_complete; + init_completion(&completion_work.done); + drbd_queue_work(work_queue, &completion_work.w); + wait_for_completion(&completion_work.done); +} + +struct drbd_resource *drbd_find_resource(const char *name) +{ + struct drbd_resource *resource; + + if (!name || !name[0]) + return NULL; + + rcu_read_lock(); + for_each_resource_rcu(resource, &drbd_resources) { + if (!strcmp(resource->name, name)) { + kref_get(&resource->kref); + goto found; + } + } + resource = NULL; +found: + rcu_read_unlock(); + return resource; +} + +struct drbd_connection *conn_get_by_addrs(void *my_addr, int my_addr_len, + void *peer_addr, int peer_addr_len) +{ + struct drbd_resource *resource; + struct drbd_connection *connection; + + rcu_read_lock(); + for_each_resource_rcu(resource, &drbd_resources) { + for_each_connection_rcu(connection, resource) { + if (connection->my_addr_len == my_addr_len && + connection->peer_addr_len == peer_addr_len && + !memcmp(&connection->my_addr, my_addr, my_addr_len) && + !memcmp(&connection->peer_addr, peer_addr, peer_addr_len)) { + kref_get(&connection->kref); + goto found; + } + } + } + connection = NULL; +found: + rcu_read_unlock(); + return connection; +} + +static int drbd_alloc_socket(struct drbd_socket *socket) +{ + socket->rbuf = (void *) __get_free_page(GFP_KERNEL); + if (!socket->rbuf) + return -ENOMEM; + socket->sbuf = (void *) __get_free_page(GFP_KERNEL); + if (!socket->sbuf) + return -ENOMEM; + return 0; +} + +static void drbd_free_socket(struct drbd_socket *socket) +{ + free_page((unsigned long) socket->sbuf); + free_page((unsigned long) socket->rbuf); +} + +void conn_free_crypto(struct drbd_connection *connection) +{ + drbd_free_sock(connection); + + crypto_free_ahash(connection->csums_tfm); + crypto_free_ahash(connection->verify_tfm); + crypto_free_shash(connection->cram_hmac_tfm); + crypto_free_ahash(connection->integrity_tfm); + crypto_free_ahash(connection->peer_integrity_tfm); + kfree(connection->int_dig_in); + kfree(connection->int_dig_vv); + + connection->csums_tfm = NULL; + connection->verify_tfm = NULL; + connection->cram_hmac_tfm = NULL; + connection->integrity_tfm = NULL; + connection->peer_integrity_tfm = NULL; + connection->int_dig_in = NULL; + connection->int_dig_vv = NULL; +} + +int set_resource_options(struct drbd_resource *resource, struct res_opts *res_opts) +{ + struct drbd_connection *connection; + cpumask_var_t new_cpu_mask; + int err; + + if (!zalloc_cpumask_var(&new_cpu_mask, GFP_KERNEL)) + return -ENOMEM; + + /* silently ignore cpu mask on UP kernel */ + if (nr_cpu_ids > 1 && res_opts->cpu_mask[0] != 0) { + err = bitmap_parse(res_opts->cpu_mask, DRBD_CPU_MASK_SIZE, + cpumask_bits(new_cpu_mask), nr_cpu_ids); + if (err == -EOVERFLOW) { + /* So what. mask it out. */ + cpumask_var_t tmp_cpu_mask; + if (zalloc_cpumask_var(&tmp_cpu_mask, GFP_KERNEL)) { + cpumask_setall(tmp_cpu_mask); + cpumask_and(new_cpu_mask, new_cpu_mask, tmp_cpu_mask); + drbd_warn(resource, "Overflow in bitmap_parse(%.12s%s), truncating to %u bits\n", + res_opts->cpu_mask, + strlen(res_opts->cpu_mask) > 12 ? "..." : "", + nr_cpu_ids); + free_cpumask_var(tmp_cpu_mask); + err = 0; + } + } + if (err) { + drbd_warn(resource, "bitmap_parse() failed with %d\n", err); + /* retcode = ERR_CPU_MASK_PARSE; */ + goto fail; + } + } + resource->res_opts = *res_opts; + if (cpumask_empty(new_cpu_mask)) + drbd_calc_cpu_mask(&new_cpu_mask); + if (!cpumask_equal(resource->cpu_mask, new_cpu_mask)) { + cpumask_copy(resource->cpu_mask, new_cpu_mask); + for_each_connection_rcu(connection, resource) { + connection->receiver.reset_cpu_mask = 1; + connection->ack_receiver.reset_cpu_mask = 1; + connection->worker.reset_cpu_mask = 1; + } + } + err = 0; + +fail: + free_cpumask_var(new_cpu_mask); + return err; + +} + +struct drbd_resource *drbd_create_resource(const char *name) +{ + struct drbd_resource *resource; + + resource = kzalloc(sizeof(struct drbd_resource), GFP_KERNEL); + if (!resource) + goto fail; + resource->name = kstrdup(name, GFP_KERNEL); + if (!resource->name) + goto fail_free_resource; + if (!zalloc_cpumask_var(&resource->cpu_mask, GFP_KERNEL)) + goto fail_free_name; + kref_init(&resource->kref); + idr_init(&resource->devices); + INIT_LIST_HEAD(&resource->connections); + resource->write_ordering = WO_BDEV_FLUSH; + list_add_tail_rcu(&resource->resources, &drbd_resources); + mutex_init(&resource->conf_update); + mutex_init(&resource->adm_mutex); + spin_lock_init(&resource->req_lock); + drbd_debugfs_resource_add(resource); + return resource; + +fail_free_name: + kfree(resource->name); +fail_free_resource: + kfree(resource); +fail: + return NULL; +} + +/* caller must be under adm_mutex */ +struct drbd_connection *conn_create(const char *name, struct res_opts *res_opts) +{ + struct drbd_resource *resource; + struct drbd_connection *connection; + + connection = kzalloc(sizeof(struct drbd_connection), GFP_KERNEL); + if (!connection) + return NULL; + + if (drbd_alloc_socket(&connection->data)) + goto fail; + if (drbd_alloc_socket(&connection->meta)) + goto fail; + + connection->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL); + if (!connection->current_epoch) + goto fail; + + INIT_LIST_HEAD(&connection->transfer_log); + + INIT_LIST_HEAD(&connection->current_epoch->list); + connection->epochs = 1; + spin_lock_init(&connection->epoch_lock); + + connection->send.seen_any_write_yet = false; + connection->send.current_epoch_nr = 0; + connection->send.current_epoch_writes = 0; + + resource = drbd_create_resource(name); + if (!resource) + goto fail; + + connection->cstate = C_STANDALONE; + mutex_init(&connection->cstate_mutex); + init_waitqueue_head(&connection->ping_wait); + idr_init(&connection->peer_devices); + + drbd_init_workqueue(&connection->sender_work); + mutex_init(&connection->data.mutex); + mutex_init(&connection->meta.mutex); + + drbd_thread_init(resource, &connection->receiver, drbd_receiver, "receiver"); + connection->receiver.connection = connection; + drbd_thread_init(resource, &connection->worker, drbd_worker, "worker"); + connection->worker.connection = connection; + drbd_thread_init(resource, &connection->ack_receiver, drbd_ack_receiver, "ack_recv"); + connection->ack_receiver.connection = connection; + + kref_init(&connection->kref); + + connection->resource = resource; + + if (set_resource_options(resource, res_opts)) + goto fail_resource; + + kref_get(&resource->kref); + list_add_tail_rcu(&connection->connections, &resource->connections); + drbd_debugfs_connection_add(connection); + return connection; + +fail_resource: + list_del(&resource->resources); + drbd_free_resource(resource); +fail: + kfree(connection->current_epoch); + drbd_free_socket(&connection->meta); + drbd_free_socket(&connection->data); + kfree(connection); + return NULL; +} + +void drbd_destroy_connection(struct kref *kref) +{ + struct drbd_connection *connection = container_of(kref, struct drbd_connection, kref); + struct drbd_resource *resource = connection->resource; + + if (atomic_read(&connection->current_epoch->epoch_size) != 0) + drbd_err(connection, "epoch_size:%d\n", atomic_read(&connection->current_epoch->epoch_size)); + kfree(connection->current_epoch); + + idr_destroy(&connection->peer_devices); + + drbd_free_socket(&connection->meta); + drbd_free_socket(&connection->data); + kfree(connection->int_dig_in); + kfree(connection->int_dig_vv); + memset(connection, 0xfc, sizeof(*connection)); + kfree(connection); + kref_put(&resource->kref, drbd_destroy_resource); +} + +static int init_submitter(struct drbd_device *device) +{ + /* opencoded create_singlethread_workqueue(), + * to be able to say "drbd%d", ..., minor */ + device->submit.wq = + alloc_ordered_workqueue("drbd%u_submit", WQ_MEM_RECLAIM, device->minor); + if (!device->submit.wq) + return -ENOMEM; + + INIT_WORK(&device->submit.worker, do_submit); + INIT_LIST_HEAD(&device->submit.writes); + return 0; +} + +enum drbd_ret_code drbd_create_device(struct drbd_config_context *adm_ctx, unsigned int minor) +{ + struct drbd_resource *resource = adm_ctx->resource; + struct drbd_connection *connection; + struct drbd_device *device; + struct drbd_peer_device *peer_device, *tmp_peer_device; + struct gendisk *disk; + struct request_queue *q; + int id; + int vnr = adm_ctx->volume; + enum drbd_ret_code err = ERR_NOMEM; + + device = minor_to_device(minor); + if (device) + return ERR_MINOR_OR_VOLUME_EXISTS; + + /* GFP_KERNEL, we are outside of all write-out paths */ + device = kzalloc(sizeof(struct drbd_device), GFP_KERNEL); + if (!device) + return ERR_NOMEM; + kref_init(&device->kref); + + kref_get(&resource->kref); + device->resource = resource; + device->minor = minor; + device->vnr = vnr; + + drbd_init_set_defaults(device); + + q = blk_alloc_queue_node(GFP_KERNEL, NUMA_NO_NODE, &resource->req_lock); + if (!q) + goto out_no_q; + device->rq_queue = q; + q->queuedata = device; + + disk = alloc_disk(1); + if (!disk) + goto out_no_disk; + device->vdisk = disk; + + set_disk_ro(disk, true); + + disk->queue = q; + disk->major = DRBD_MAJOR; + disk->first_minor = minor; + disk->fops = &drbd_ops; + sprintf(disk->disk_name, "drbd%d", minor); + disk->private_data = device; + + device->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor)); + /* we have no partitions. we contain only ourselves. */ + device->this_bdev->bd_contains = device->this_bdev; + + q->backing_dev_info->congested_fn = drbd_congested; + q->backing_dev_info->congested_data = device; + + blk_queue_make_request(q, drbd_make_request); + blk_queue_write_cache(q, true, true); + /* Setting the max_hw_sectors to an odd value of 8kibyte here + This triggers a max_bio_size message upon first attach or connect */ + blk_queue_max_hw_sectors(q, DRBD_MAX_BIO_SIZE_SAFE >> 8); + + device->md_io.page = alloc_page(GFP_KERNEL); + if (!device->md_io.page) + goto out_no_io_page; + + if (drbd_bm_init(device)) + goto out_no_bitmap; + device->read_requests = RB_ROOT; + device->write_requests = RB_ROOT; + + id = idr_alloc(&drbd_devices, device, minor, minor + 1, GFP_KERNEL); + if (id < 0) { + if (id == -ENOSPC) + err = ERR_MINOR_OR_VOLUME_EXISTS; + goto out_no_minor_idr; + } + kref_get(&device->kref); + + id = idr_alloc(&resource->devices, device, vnr, vnr + 1, GFP_KERNEL); + if (id < 0) { + if (id == -ENOSPC) + err = ERR_MINOR_OR_VOLUME_EXISTS; + goto out_idr_remove_minor; + } + kref_get(&device->kref); + + INIT_LIST_HEAD(&device->peer_devices); + INIT_LIST_HEAD(&device->pending_bitmap_io); + for_each_connection(connection, resource) { + peer_device = kzalloc(sizeof(struct drbd_peer_device), GFP_KERNEL); + if (!peer_device) + goto out_idr_remove_from_resource; + peer_device->connection = connection; + peer_device->device = device; + + list_add(&peer_device->peer_devices, &device->peer_devices); + kref_get(&device->kref); + + id = idr_alloc(&connection->peer_devices, peer_device, vnr, vnr + 1, GFP_KERNEL); + if (id < 0) { + if (id == -ENOSPC) + err = ERR_INVALID_REQUEST; + goto out_idr_remove_from_resource; + } + kref_get(&connection->kref); + INIT_WORK(&peer_device->send_acks_work, drbd_send_acks_wf); + } + + if (init_submitter(device)) { + err = ERR_NOMEM; + goto out_idr_remove_vol; + } + + add_disk(disk); + + /* inherit the connection state */ + device->state.conn = first_connection(resource)->cstate; + if (device->state.conn == C_WF_REPORT_PARAMS) { + for_each_peer_device(peer_device, device) + drbd_connected(peer_device); + } + /* move to create_peer_device() */ + for_each_peer_device(peer_device, device) + drbd_debugfs_peer_device_add(peer_device); + drbd_debugfs_device_add(device); + return NO_ERROR; + +out_idr_remove_vol: + idr_remove(&connection->peer_devices, vnr); +out_idr_remove_from_resource: + for_each_connection(connection, resource) { + peer_device = idr_remove(&connection->peer_devices, vnr); + if (peer_device) + kref_put(&connection->kref, drbd_destroy_connection); + } + for_each_peer_device_safe(peer_device, tmp_peer_device, device) { + list_del(&peer_device->peer_devices); + kfree(peer_device); + } + idr_remove(&resource->devices, vnr); +out_idr_remove_minor: + idr_remove(&drbd_devices, minor); + synchronize_rcu(); +out_no_minor_idr: + drbd_bm_cleanup(device); +out_no_bitmap: + __free_page(device->md_io.page); +out_no_io_page: + put_disk(disk); +out_no_disk: + blk_cleanup_queue(q); +out_no_q: + kref_put(&resource->kref, drbd_destroy_resource); + kfree(device); + return err; +} + +void drbd_delete_device(struct drbd_device *device) +{ + struct drbd_resource *resource = device->resource; + struct drbd_connection *connection; + struct drbd_peer_device *peer_device; + + /* move to free_peer_device() */ + for_each_peer_device(peer_device, device) + drbd_debugfs_peer_device_cleanup(peer_device); + drbd_debugfs_device_cleanup(device); + for_each_connection(connection, resource) { + idr_remove(&connection->peer_devices, device->vnr); + kref_put(&device->kref, drbd_destroy_device); + } + idr_remove(&resource->devices, device->vnr); + kref_put(&device->kref, drbd_destroy_device); + idr_remove(&drbd_devices, device_to_minor(device)); + kref_put(&device->kref, drbd_destroy_device); + del_gendisk(device->vdisk); + synchronize_rcu(); + kref_put(&device->kref, drbd_destroy_device); +} + +static int __init drbd_init(void) +{ + int err; + + if (drbd_minor_count < DRBD_MINOR_COUNT_MIN || drbd_minor_count > DRBD_MINOR_COUNT_MAX) { + pr_err("invalid minor_count (%d)\n", drbd_minor_count); +#ifdef MODULE + return -EINVAL; +#else + drbd_minor_count = DRBD_MINOR_COUNT_DEF; +#endif + } + + err = register_blkdev(DRBD_MAJOR, "drbd"); + if (err) { + pr_err("unable to register block device major %d\n", + DRBD_MAJOR); + return err; + } + + /* + * allocate all necessary structs + */ + init_waitqueue_head(&drbd_pp_wait); + + drbd_proc = NULL; /* play safe for drbd_cleanup */ + idr_init(&drbd_devices); + + mutex_init(&resources_mutex); + INIT_LIST_HEAD(&drbd_resources); + + err = drbd_genl_register(); + if (err) { + pr_err("unable to register generic netlink family\n"); + goto fail; + } + + err = drbd_create_mempools(); + if (err) + goto fail; + + err = -ENOMEM; + drbd_proc = proc_create_single("drbd", S_IFREG | 0444 , NULL, drbd_seq_show); + if (!drbd_proc) { + pr_err("unable to register proc file\n"); + goto fail; + } + + retry.wq = create_singlethread_workqueue("drbd-reissue"); + if (!retry.wq) { + pr_err("unable to create retry workqueue\n"); + goto fail; + } + INIT_WORK(&retry.worker, do_retry); + spin_lock_init(&retry.lock); + INIT_LIST_HEAD(&retry.writes); + + if (drbd_debugfs_init()) + pr_notice("failed to initialize debugfs -- will not be available\n"); + + pr_info("initialized. " + "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n", + API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX); + pr_info("%s\n", drbd_buildtag()); + pr_info("registered as block device major %d\n", DRBD_MAJOR); + return 0; /* Success! */ + +fail: + drbd_cleanup(); + if (err == -ENOMEM) + pr_err("ran out of memory\n"); + else + pr_err("initialization failure\n"); + return err; +} + +static void drbd_free_one_sock(struct drbd_socket *ds) +{ + struct socket *s; + mutex_lock(&ds->mutex); + s = ds->socket; + ds->socket = NULL; + mutex_unlock(&ds->mutex); + if (s) { + /* so debugfs does not need to mutex_lock() */ + synchronize_rcu(); + kernel_sock_shutdown(s, SHUT_RDWR); + sock_release(s); + } +} + +void drbd_free_sock(struct drbd_connection *connection) +{ + if (connection->data.socket) + drbd_free_one_sock(&connection->data); + if (connection->meta.socket) + drbd_free_one_sock(&connection->meta); +} + +/* meta data management */ + +void conn_md_sync(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) { + struct drbd_device *device = peer_device->device; + + kref_get(&device->kref); + rcu_read_unlock(); + drbd_md_sync(device); + kref_put(&device->kref, drbd_destroy_device); + rcu_read_lock(); + } + rcu_read_unlock(); +} + +/* aligned 4kByte */ +struct meta_data_on_disk { + u64 la_size_sect; /* last agreed size. */ + u64 uuid[UI_SIZE]; /* UUIDs. */ + u64 device_uuid; + u64 reserved_u64_1; + u32 flags; /* MDF */ + u32 magic; + u32 md_size_sect; + u32 al_offset; /* offset to this block */ + u32 al_nr_extents; /* important for restoring the AL (userspace) */ + /* `-- act_log->nr_elements <-- ldev->dc.al_extents */ + u32 bm_offset; /* offset to the bitmap, from here */ + u32 bm_bytes_per_bit; /* BM_BLOCK_SIZE */ + u32 la_peer_max_bio_size; /* last peer max_bio_size */ + + /* see al_tr_number_to_on_disk_sector() */ + u32 al_stripes; + u32 al_stripe_size_4k; + + u8 reserved_u8[4096 - (7*8 + 10*4)]; +} __packed; + + + +void drbd_md_write(struct drbd_device *device, void *b) +{ + struct meta_data_on_disk *buffer = b; + sector_t sector; + int i; + + memset(buffer, 0, sizeof(*buffer)); + + buffer->la_size_sect = cpu_to_be64(drbd_get_capacity(device->this_bdev)); + for (i = UI_CURRENT; i < UI_SIZE; i++) + buffer->uuid[i] = cpu_to_be64(device->ldev->md.uuid[i]); + buffer->flags = cpu_to_be32(device->ldev->md.flags); + buffer->magic = cpu_to_be32(DRBD_MD_MAGIC_84_UNCLEAN); + + buffer->md_size_sect = cpu_to_be32(device->ldev->md.md_size_sect); + buffer->al_offset = cpu_to_be32(device->ldev->md.al_offset); + buffer->al_nr_extents = cpu_to_be32(device->act_log->nr_elements); + buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE); + buffer->device_uuid = cpu_to_be64(device->ldev->md.device_uuid); + + buffer->bm_offset = cpu_to_be32(device->ldev->md.bm_offset); + buffer->la_peer_max_bio_size = cpu_to_be32(device->peer_max_bio_size); + + buffer->al_stripes = cpu_to_be32(device->ldev->md.al_stripes); + buffer->al_stripe_size_4k = cpu_to_be32(device->ldev->md.al_stripe_size_4k); + + D_ASSERT(device, drbd_md_ss(device->ldev) == device->ldev->md.md_offset); + sector = device->ldev->md.md_offset; + + if (drbd_md_sync_page_io(device, device->ldev, sector, REQ_OP_WRITE)) { + /* this was a try anyways ... */ + drbd_err(device, "meta data update failed!\n"); + drbd_chk_io_error(device, 1, DRBD_META_IO_ERROR); + } +} + +/** + * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set + * @device: DRBD device. + */ +void drbd_md_sync(struct drbd_device *device) +{ + struct meta_data_on_disk *buffer; + + /* Don't accidentally change the DRBD meta data layout. */ + BUILD_BUG_ON(UI_SIZE != 4); + BUILD_BUG_ON(sizeof(struct meta_data_on_disk) != 4096); + + del_timer(&device->md_sync_timer); + /* timer may be rearmed by drbd_md_mark_dirty() now. */ + if (!test_and_clear_bit(MD_DIRTY, &device->flags)) + return; + + /* We use here D_FAILED and not D_ATTACHING because we try to write + * metadata even if we detach due to a disk failure! */ + if (!get_ldev_if_state(device, D_FAILED)) + return; + + buffer = drbd_md_get_buffer(device, __func__); + if (!buffer) + goto out; + + drbd_md_write(device, buffer); + + /* Update device->ldev->md.la_size_sect, + * since we updated it on metadata. */ + device->ldev->md.la_size_sect = drbd_get_capacity(device->this_bdev); + + drbd_md_put_buffer(device); +out: + put_ldev(device); +} + +static int check_activity_log_stripe_size(struct drbd_device *device, + struct meta_data_on_disk *on_disk, + struct drbd_md *in_core) +{ + u32 al_stripes = be32_to_cpu(on_disk->al_stripes); + u32 al_stripe_size_4k = be32_to_cpu(on_disk->al_stripe_size_4k); + u64 al_size_4k; + + /* both not set: default to old fixed size activity log */ + if (al_stripes == 0 && al_stripe_size_4k == 0) { + al_stripes = 1; + al_stripe_size_4k = MD_32kB_SECT/8; + } + + /* some paranoia plausibility checks */ + + /* we need both values to be set */ + if (al_stripes == 0 || al_stripe_size_4k == 0) + goto err; + + al_size_4k = (u64)al_stripes * al_stripe_size_4k; + + /* Upper limit of activity log area, to avoid potential overflow + * problems in al_tr_number_to_on_disk_sector(). As right now, more + * than 72 * 4k blocks total only increases the amount of history, + * limiting this arbitrarily to 16 GB is not a real limitation ;-) */ + if (al_size_4k > (16 * 1024 * 1024/4)) + goto err; + + /* Lower limit: we need at least 8 transaction slots (32kB) + * to not break existing setups */ + if (al_size_4k < MD_32kB_SECT/8) + goto err; + + in_core->al_stripe_size_4k = al_stripe_size_4k; + in_core->al_stripes = al_stripes; + in_core->al_size_4k = al_size_4k; + + return 0; +err: + drbd_err(device, "invalid activity log striping: al_stripes=%u, al_stripe_size_4k=%u\n", + al_stripes, al_stripe_size_4k); + return -EINVAL; +} + +static int check_offsets_and_sizes(struct drbd_device *device, struct drbd_backing_dev *bdev) +{ + sector_t capacity = drbd_get_capacity(bdev->md_bdev); + struct drbd_md *in_core = &bdev->md; + s32 on_disk_al_sect; + s32 on_disk_bm_sect; + + /* The on-disk size of the activity log, calculated from offsets, and + * the size of the activity log calculated from the stripe settings, + * should match. + * Though we could relax this a bit: it is ok, if the striped activity log + * fits in the available on-disk activity log size. + * Right now, that would break how resize is implemented. + * TODO: make drbd_determine_dev_size() (and the drbdmeta tool) aware + * of possible unused padding space in the on disk layout. */ + if (in_core->al_offset < 0) { + if (in_core->bm_offset > in_core->al_offset) + goto err; + on_disk_al_sect = -in_core->al_offset; + on_disk_bm_sect = in_core->al_offset - in_core->bm_offset; + } else { + if (in_core->al_offset != MD_4kB_SECT) + goto err; + if (in_core->bm_offset < in_core->al_offset + in_core->al_size_4k * MD_4kB_SECT) + goto err; + + on_disk_al_sect = in_core->bm_offset - MD_4kB_SECT; + on_disk_bm_sect = in_core->md_size_sect - in_core->bm_offset; + } + + /* old fixed size meta data is exactly that: fixed. */ + if (in_core->meta_dev_idx >= 0) { + if (in_core->md_size_sect != MD_128MB_SECT + || in_core->al_offset != MD_4kB_SECT + || in_core->bm_offset != MD_4kB_SECT + MD_32kB_SECT + || in_core->al_stripes != 1 + || in_core->al_stripe_size_4k != MD_32kB_SECT/8) + goto err; + } + + if (capacity < in_core->md_size_sect) + goto err; + if (capacity - in_core->md_size_sect < drbd_md_first_sector(bdev)) + goto err; + + /* should be aligned, and at least 32k */ + if ((on_disk_al_sect & 7) || (on_disk_al_sect < MD_32kB_SECT)) + goto err; + + /* should fit (for now: exactly) into the available on-disk space; + * overflow prevention is in check_activity_log_stripe_size() above. */ + if (on_disk_al_sect != in_core->al_size_4k * MD_4kB_SECT) + goto err; + + /* again, should be aligned */ + if (in_core->bm_offset & 7) + goto err; + + /* FIXME check for device grow with flex external meta data? */ + + /* can the available bitmap space cover the last agreed device size? */ + if (on_disk_bm_sect < (in_core->la_size_sect+7)/MD_4kB_SECT/8/512) + goto err; + + return 0; + +err: + drbd_err(device, "meta data offsets don't make sense: idx=%d " + "al_s=%u, al_sz4k=%u, al_offset=%d, bm_offset=%d, " + "md_size_sect=%u, la_size=%llu, md_capacity=%llu\n", + in_core->meta_dev_idx, + in_core->al_stripes, in_core->al_stripe_size_4k, + in_core->al_offset, in_core->bm_offset, in_core->md_size_sect, + (unsigned long long)in_core->la_size_sect, + (unsigned long long)capacity); + + return -EINVAL; +} + + +/** + * drbd_md_read() - Reads in the meta data super block + * @device: DRBD device. + * @bdev: Device from which the meta data should be read in. + * + * Return NO_ERROR on success, and an enum drbd_ret_code in case + * something goes wrong. + * + * Called exactly once during drbd_adm_attach(), while still being D_DISKLESS, + * even before @bdev is assigned to @device->ldev. + */ +int drbd_md_read(struct drbd_device *device, struct drbd_backing_dev *bdev) +{ + struct meta_data_on_disk *buffer; + u32 magic, flags; + int i, rv = NO_ERROR; + + if (device->state.disk != D_DISKLESS) + return ERR_DISK_CONFIGURED; + + buffer = drbd_md_get_buffer(device, __func__); + if (!buffer) + return ERR_NOMEM; + + /* First, figure out where our meta data superblock is located, + * and read it. */ + bdev->md.meta_dev_idx = bdev->disk_conf->meta_dev_idx; + bdev->md.md_offset = drbd_md_ss(bdev); + /* Even for (flexible or indexed) external meta data, + * initially restrict us to the 4k superblock for now. + * Affects the paranoia out-of-range access check in drbd_md_sync_page_io(). */ + bdev->md.md_size_sect = 8; + + if (drbd_md_sync_page_io(device, bdev, bdev->md.md_offset, + REQ_OP_READ)) { + /* NOTE: can't do normal error processing here as this is + called BEFORE disk is attached */ + drbd_err(device, "Error while reading metadata.\n"); + rv = ERR_IO_MD_DISK; + goto err; + } + + magic = be32_to_cpu(buffer->magic); + flags = be32_to_cpu(buffer->flags); + if (magic == DRBD_MD_MAGIC_84_UNCLEAN || + (magic == DRBD_MD_MAGIC_08 && !(flags & MDF_AL_CLEAN))) { + /* btw: that's Activity Log clean, not "all" clean. */ + drbd_err(device, "Found unclean meta data. Did you \"drbdadm apply-al\"?\n"); + rv = ERR_MD_UNCLEAN; + goto err; + } + + rv = ERR_MD_INVALID; + if (magic != DRBD_MD_MAGIC_08) { + if (magic == DRBD_MD_MAGIC_07) + drbd_err(device, "Found old (0.7) meta data magic. Did you \"drbdadm create-md\"?\n"); + else + drbd_err(device, "Meta data magic not found. Did you \"drbdadm create-md\"?\n"); + goto err; + } + + if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) { + drbd_err(device, "unexpected bm_bytes_per_bit: %u (expected %u)\n", + be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE); + goto err; + } + + + /* convert to in_core endian */ + bdev->md.la_size_sect = be64_to_cpu(buffer->la_size_sect); + for (i = UI_CURRENT; i < UI_SIZE; i++) + bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]); + bdev->md.flags = be32_to_cpu(buffer->flags); + bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid); + + bdev->md.md_size_sect = be32_to_cpu(buffer->md_size_sect); + bdev->md.al_offset = be32_to_cpu(buffer->al_offset); + bdev->md.bm_offset = be32_to_cpu(buffer->bm_offset); + + if (check_activity_log_stripe_size(device, buffer, &bdev->md)) + goto err; + if (check_offsets_and_sizes(device, bdev)) + goto err; + + if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) { + drbd_err(device, "unexpected bm_offset: %d (expected %d)\n", + be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset); + goto err; + } + if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) { + drbd_err(device, "unexpected md_size: %u (expected %u)\n", + be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect); + goto err; + } + + rv = NO_ERROR; + + spin_lock_irq(&device->resource->req_lock); + if (device->state.conn < C_CONNECTED) { + unsigned int peer; + peer = be32_to_cpu(buffer->la_peer_max_bio_size); + peer = max(peer, DRBD_MAX_BIO_SIZE_SAFE); + device->peer_max_bio_size = peer; + } + spin_unlock_irq(&device->resource->req_lock); + + err: + drbd_md_put_buffer(device); + + return rv; +} + +/** + * drbd_md_mark_dirty() - Mark meta data super block as dirty + * @device: DRBD device. + * + * Call this function if you change anything that should be written to + * the meta-data super block. This function sets MD_DIRTY, and starts a + * timer that ensures that within five seconds you have to call drbd_md_sync(). + */ +#ifdef DEBUG +void drbd_md_mark_dirty_(struct drbd_device *device, unsigned int line, const char *func) +{ + if (!test_and_set_bit(MD_DIRTY, &device->flags)) { + mod_timer(&device->md_sync_timer, jiffies + HZ); + device->last_md_mark_dirty.line = line; + device->last_md_mark_dirty.func = func; + } +} +#else +void drbd_md_mark_dirty(struct drbd_device *device) +{ + if (!test_and_set_bit(MD_DIRTY, &device->flags)) + mod_timer(&device->md_sync_timer, jiffies + 5*HZ); +} +#endif + +void drbd_uuid_move_history(struct drbd_device *device) __must_hold(local) +{ + int i; + + for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++) + device->ldev->md.uuid[i+1] = device->ldev->md.uuid[i]; +} + +void __drbd_uuid_set(struct drbd_device *device, int idx, u64 val) __must_hold(local) +{ + if (idx == UI_CURRENT) { + if (device->state.role == R_PRIMARY) + val |= 1; + else + val &= ~((u64)1); + + drbd_set_ed_uuid(device, val); + } + + device->ldev->md.uuid[idx] = val; + drbd_md_mark_dirty(device); +} + +void _drbd_uuid_set(struct drbd_device *device, int idx, u64 val) __must_hold(local) +{ + unsigned long flags; + spin_lock_irqsave(&device->ldev->md.uuid_lock, flags); + __drbd_uuid_set(device, idx, val); + spin_unlock_irqrestore(&device->ldev->md.uuid_lock, flags); +} + +void drbd_uuid_set(struct drbd_device *device, int idx, u64 val) __must_hold(local) +{ + unsigned long flags; + spin_lock_irqsave(&device->ldev->md.uuid_lock, flags); + if (device->ldev->md.uuid[idx]) { + drbd_uuid_move_history(device); + device->ldev->md.uuid[UI_HISTORY_START] = device->ldev->md.uuid[idx]; + } + __drbd_uuid_set(device, idx, val); + spin_unlock_irqrestore(&device->ldev->md.uuid_lock, flags); +} + +/** + * drbd_uuid_new_current() - Creates a new current UUID + * @device: DRBD device. + * + * Creates a new current UUID, and rotates the old current UUID into + * the bitmap slot. Causes an incremental resync upon next connect. + */ +void drbd_uuid_new_current(struct drbd_device *device) __must_hold(local) +{ + u64 val; + unsigned long long bm_uuid; + + get_random_bytes(&val, sizeof(u64)); + + spin_lock_irq(&device->ldev->md.uuid_lock); + bm_uuid = device->ldev->md.uuid[UI_BITMAP]; + + if (bm_uuid) + drbd_warn(device, "bm UUID was already set: %llX\n", bm_uuid); + + device->ldev->md.uuid[UI_BITMAP] = device->ldev->md.uuid[UI_CURRENT]; + __drbd_uuid_set(device, UI_CURRENT, val); + spin_unlock_irq(&device->ldev->md.uuid_lock); + + drbd_print_uuids(device, "new current UUID"); + /* get it to stable storage _now_ */ + drbd_md_sync(device); +} + +void drbd_uuid_set_bm(struct drbd_device *device, u64 val) __must_hold(local) +{ + unsigned long flags; + if (device->ldev->md.uuid[UI_BITMAP] == 0 && val == 0) + return; + + spin_lock_irqsave(&device->ldev->md.uuid_lock, flags); + if (val == 0) { + drbd_uuid_move_history(device); + device->ldev->md.uuid[UI_HISTORY_START] = device->ldev->md.uuid[UI_BITMAP]; + device->ldev->md.uuid[UI_BITMAP] = 0; + } else { + unsigned long long bm_uuid = device->ldev->md.uuid[UI_BITMAP]; + if (bm_uuid) + drbd_warn(device, "bm UUID was already set: %llX\n", bm_uuid); + + device->ldev->md.uuid[UI_BITMAP] = val & ~((u64)1); + } + spin_unlock_irqrestore(&device->ldev->md.uuid_lock, flags); + + drbd_md_mark_dirty(device); +} + +/** + * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io() + * @device: DRBD device. + * + * Sets all bits in the bitmap and writes the whole bitmap to stable storage. + */ +int drbd_bmio_set_n_write(struct drbd_device *device) __must_hold(local) +{ + int rv = -EIO; + + drbd_md_set_flag(device, MDF_FULL_SYNC); + drbd_md_sync(device); + drbd_bm_set_all(device); + + rv = drbd_bm_write(device); + + if (!rv) { + drbd_md_clear_flag(device, MDF_FULL_SYNC); + drbd_md_sync(device); + } + + return rv; +} + +/** + * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io() + * @device: DRBD device. + * + * Clears all bits in the bitmap and writes the whole bitmap to stable storage. + */ +int drbd_bmio_clear_n_write(struct drbd_device *device) __must_hold(local) +{ + drbd_resume_al(device); + drbd_bm_clear_all(device); + return drbd_bm_write(device); +} + +static int w_bitmap_io(struct drbd_work *w, int unused) +{ + struct drbd_device *device = + container_of(w, struct drbd_device, bm_io_work.w); + struct bm_io_work *work = &device->bm_io_work; + int rv = -EIO; + + if (work->flags != BM_LOCKED_CHANGE_ALLOWED) { + int cnt = atomic_read(&device->ap_bio_cnt); + if (cnt) + drbd_err(device, "FIXME: ap_bio_cnt %d, expected 0; queued for '%s'\n", + cnt, work->why); + } + + if (get_ldev(device)) { + drbd_bm_lock(device, work->why, work->flags); + rv = work->io_fn(device); + drbd_bm_unlock(device); + put_ldev(device); + } + + clear_bit_unlock(BITMAP_IO, &device->flags); + wake_up(&device->misc_wait); + + if (work->done) + work->done(device, rv); + + clear_bit(BITMAP_IO_QUEUED, &device->flags); + work->why = NULL; + work->flags = 0; + + return 0; +} + +/** + * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap + * @device: DRBD device. + * @io_fn: IO callback to be called when bitmap IO is possible + * @done: callback to be called after the bitmap IO was performed + * @why: Descriptive text of the reason for doing the IO + * + * While IO on the bitmap happens we freeze application IO thus we ensure + * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be + * called from worker context. It MUST NOT be used while a previous such + * work is still pending! + * + * Its worker function encloses the call of io_fn() by get_ldev() and + * put_ldev(). + */ +void drbd_queue_bitmap_io(struct drbd_device *device, + int (*io_fn)(struct drbd_device *), + void (*done)(struct drbd_device *, int), + char *why, enum bm_flag flags) +{ + D_ASSERT(device, current == first_peer_device(device)->connection->worker.task); + + D_ASSERT(device, !test_bit(BITMAP_IO_QUEUED, &device->flags)); + D_ASSERT(device, !test_bit(BITMAP_IO, &device->flags)); + D_ASSERT(device, list_empty(&device->bm_io_work.w.list)); + if (device->bm_io_work.why) + drbd_err(device, "FIXME going to queue '%s' but '%s' still pending?\n", + why, device->bm_io_work.why); + + device->bm_io_work.io_fn = io_fn; + device->bm_io_work.done = done; + device->bm_io_work.why = why; + device->bm_io_work.flags = flags; + + spin_lock_irq(&device->resource->req_lock); + set_bit(BITMAP_IO, &device->flags); + /* don't wait for pending application IO if the caller indicates that + * application IO does not conflict anyways. */ + if (flags == BM_LOCKED_CHANGE_ALLOWED || atomic_read(&device->ap_bio_cnt) == 0) { + if (!test_and_set_bit(BITMAP_IO_QUEUED, &device->flags)) + drbd_queue_work(&first_peer_device(device)->connection->sender_work, + &device->bm_io_work.w); + } + spin_unlock_irq(&device->resource->req_lock); +} + +/** + * drbd_bitmap_io() - Does an IO operation on the whole bitmap + * @device: DRBD device. + * @io_fn: IO callback to be called when bitmap IO is possible + * @why: Descriptive text of the reason for doing the IO + * + * freezes application IO while that the actual IO operations runs. This + * functions MAY NOT be called from worker context. + */ +int drbd_bitmap_io(struct drbd_device *device, int (*io_fn)(struct drbd_device *), + char *why, enum bm_flag flags) +{ + /* Only suspend io, if some operation is supposed to be locked out */ + const bool do_suspend_io = flags & (BM_DONT_CLEAR|BM_DONT_SET|BM_DONT_TEST); + int rv; + + D_ASSERT(device, current != first_peer_device(device)->connection->worker.task); + + if (do_suspend_io) + drbd_suspend_io(device); + + drbd_bm_lock(device, why, flags); + rv = io_fn(device); + drbd_bm_unlock(device); + + if (do_suspend_io) + drbd_resume_io(device); + + return rv; +} + +void drbd_md_set_flag(struct drbd_device *device, int flag) __must_hold(local) +{ + if ((device->ldev->md.flags & flag) != flag) { + drbd_md_mark_dirty(device); + device->ldev->md.flags |= flag; + } +} + +void drbd_md_clear_flag(struct drbd_device *device, int flag) __must_hold(local) +{ + if ((device->ldev->md.flags & flag) != 0) { + drbd_md_mark_dirty(device); + device->ldev->md.flags &= ~flag; + } +} +int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag) +{ + return (bdev->md.flags & flag) != 0; +} + +static void md_sync_timer_fn(struct timer_list *t) +{ + struct drbd_device *device = from_timer(device, t, md_sync_timer); + drbd_device_post_work(device, MD_SYNC); +} + +const char *cmdname(enum drbd_packet cmd) +{ + /* THINK may need to become several global tables + * when we want to support more than + * one PRO_VERSION */ + static const char *cmdnames[] = { + [P_DATA] = "Data", + [P_WSAME] = "WriteSame", + [P_TRIM] = "Trim", + [P_DATA_REPLY] = "DataReply", + [P_RS_DATA_REPLY] = "RSDataReply", + [P_BARRIER] = "Barrier", + [P_BITMAP] = "ReportBitMap", + [P_BECOME_SYNC_TARGET] = "BecomeSyncTarget", + [P_BECOME_SYNC_SOURCE] = "BecomeSyncSource", + [P_UNPLUG_REMOTE] = "UnplugRemote", + [P_DATA_REQUEST] = "DataRequest", + [P_RS_DATA_REQUEST] = "RSDataRequest", + [P_SYNC_PARAM] = "SyncParam", + [P_SYNC_PARAM89] = "SyncParam89", + [P_PROTOCOL] = "ReportProtocol", + [P_UUIDS] = "ReportUUIDs", + [P_SIZES] = "ReportSizes", + [P_STATE] = "ReportState", + [P_SYNC_UUID] = "ReportSyncUUID", + [P_AUTH_CHALLENGE] = "AuthChallenge", + [P_AUTH_RESPONSE] = "AuthResponse", + [P_PING] = "Ping", + [P_PING_ACK] = "PingAck", + [P_RECV_ACK] = "RecvAck", + [P_WRITE_ACK] = "WriteAck", + [P_RS_WRITE_ACK] = "RSWriteAck", + [P_SUPERSEDED] = "Superseded", + [P_NEG_ACK] = "NegAck", + [P_NEG_DREPLY] = "NegDReply", + [P_NEG_RS_DREPLY] = "NegRSDReply", + [P_BARRIER_ACK] = "BarrierAck", + [P_STATE_CHG_REQ] = "StateChgRequest", + [P_STATE_CHG_REPLY] = "StateChgReply", + [P_OV_REQUEST] = "OVRequest", + [P_OV_REPLY] = "OVReply", + [P_OV_RESULT] = "OVResult", + [P_CSUM_RS_REQUEST] = "CsumRSRequest", + [P_RS_IS_IN_SYNC] = "CsumRSIsInSync", + [P_COMPRESSED_BITMAP] = "CBitmap", + [P_DELAY_PROBE] = "DelayProbe", + [P_OUT_OF_SYNC] = "OutOfSync", + [P_RETRY_WRITE] = "RetryWrite", + [P_RS_CANCEL] = "RSCancel", + [P_CONN_ST_CHG_REQ] = "conn_st_chg_req", + [P_CONN_ST_CHG_REPLY] = "conn_st_chg_reply", + [P_RETRY_WRITE] = "retry_write", + [P_PROTOCOL_UPDATE] = "protocol_update", + [P_RS_THIN_REQ] = "rs_thin_req", + [P_RS_DEALLOCATED] = "rs_deallocated", + + /* enum drbd_packet, but not commands - obsoleted flags: + * P_MAY_IGNORE + * P_MAX_OPT_CMD + */ + }; + + /* too big for the array: 0xfffX */ + if (cmd == P_INITIAL_META) + return "InitialMeta"; + if (cmd == P_INITIAL_DATA) + return "InitialData"; + if (cmd == P_CONNECTION_FEATURES) + return "ConnectionFeatures"; + if (cmd >= ARRAY_SIZE(cmdnames)) + return "Unknown"; + return cmdnames[cmd]; +} + +/** + * drbd_wait_misc - wait for a request to make progress + * @device: device associated with the request + * @i: the struct drbd_interval embedded in struct drbd_request or + * struct drbd_peer_request + */ +int drbd_wait_misc(struct drbd_device *device, struct drbd_interval *i) +{ + struct net_conf *nc; + DEFINE_WAIT(wait); + long timeout; + + rcu_read_lock(); + nc = rcu_dereference(first_peer_device(device)->connection->net_conf); + if (!nc) { + rcu_read_unlock(); + return -ETIMEDOUT; + } + timeout = nc->ko_count ? nc->timeout * HZ / 10 * nc->ko_count : MAX_SCHEDULE_TIMEOUT; + rcu_read_unlock(); + + /* Indicate to wake up device->misc_wait on progress. */ + i->waiting = true; + prepare_to_wait(&device->misc_wait, &wait, TASK_INTERRUPTIBLE); + spin_unlock_irq(&device->resource->req_lock); + timeout = schedule_timeout(timeout); + finish_wait(&device->misc_wait, &wait); + spin_lock_irq(&device->resource->req_lock); + if (!timeout || device->state.conn < C_CONNECTED) + return -ETIMEDOUT; + if (signal_pending(current)) + return -ERESTARTSYS; + return 0; +} + +void lock_all_resources(void) +{ + struct drbd_resource *resource; + int __maybe_unused i = 0; + + mutex_lock(&resources_mutex); + local_irq_disable(); + for_each_resource(resource, &drbd_resources) + spin_lock_nested(&resource->req_lock, i++); +} + +void unlock_all_resources(void) +{ + struct drbd_resource *resource; + + for_each_resource(resource, &drbd_resources) + spin_unlock(&resource->req_lock); + local_irq_enable(); + mutex_unlock(&resources_mutex); +} + +#ifdef CONFIG_DRBD_FAULT_INJECTION +/* Fault insertion support including random number generator shamelessly + * stolen from kernel/rcutorture.c */ +struct fault_random_state { + unsigned long state; + unsigned long count; +}; + +#define FAULT_RANDOM_MULT 39916801 /* prime */ +#define FAULT_RANDOM_ADD 479001701 /* prime */ +#define FAULT_RANDOM_REFRESH 10000 + +/* + * Crude but fast random-number generator. Uses a linear congruential + * generator, with occasional help from get_random_bytes(). + */ +static unsigned long +_drbd_fault_random(struct fault_random_state *rsp) +{ + long refresh; + + if (!rsp->count--) { + get_random_bytes(&refresh, sizeof(refresh)); + rsp->state += refresh; + rsp->count = FAULT_RANDOM_REFRESH; + } + rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD; + return swahw32(rsp->state); +} + +static char * +_drbd_fault_str(unsigned int type) { + static char *_faults[] = { + [DRBD_FAULT_MD_WR] = "Meta-data write", + [DRBD_FAULT_MD_RD] = "Meta-data read", + [DRBD_FAULT_RS_WR] = "Resync write", + [DRBD_FAULT_RS_RD] = "Resync read", + [DRBD_FAULT_DT_WR] = "Data write", + [DRBD_FAULT_DT_RD] = "Data read", + [DRBD_FAULT_DT_RA] = "Data read ahead", + [DRBD_FAULT_BM_ALLOC] = "BM allocation", + [DRBD_FAULT_AL_EE] = "EE allocation", + [DRBD_FAULT_RECEIVE] = "receive data corruption", + }; + + return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**"; +} + +unsigned int +_drbd_insert_fault(struct drbd_device *device, unsigned int type) +{ + static struct fault_random_state rrs = {0, 0}; + + unsigned int ret = ( + (drbd_fault_devs == 0 || + ((1 << device_to_minor(device)) & drbd_fault_devs) != 0) && + (((_drbd_fault_random(&rrs) % 100) + 1) <= drbd_fault_rate)); + + if (ret) { + drbd_fault_count++; + + if (__ratelimit(&drbd_ratelimit_state)) + drbd_warn(device, "***Simulating %s failure\n", + _drbd_fault_str(type)); + } + + return ret; +} +#endif + +const char *drbd_buildtag(void) +{ + /* DRBD built from external sources has here a reference to the + git hash of the source code. */ + + static char buildtag[38] = "\0uilt-in"; + + if (buildtag[0] == 0) { +#ifdef MODULE + sprintf(buildtag, "srcversion: %-24s", THIS_MODULE->srcversion); +#else + buildtag[0] = 'b'; +#endif + } + + return buildtag; +} + +module_init(drbd_init) +module_exit(drbd_cleanup) + +EXPORT_SYMBOL(drbd_conn_str); +EXPORT_SYMBOL(drbd_role_str); +EXPORT_SYMBOL(drbd_disk_str); +EXPORT_SYMBOL(drbd_set_st_err_str); |