| /* |
| drbd_receiver.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>. |
| |
| drbd is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| drbd is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with drbd; see the file COPYING. If not, write to |
| the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. |
| */ |
| |
| |
| #include <linux/module.h> |
| |
| #include <asm/uaccess.h> |
| #include <net/sock.h> |
| |
| #include <linux/drbd.h> |
| #include <linux/fs.h> |
| #include <linux/file.h> |
| #include <linux/in.h> |
| #include <linux/mm.h> |
| #include <linux/memcontrol.h> |
| #include <linux/mm_inline.h> |
| #include <linux/slab.h> |
| #include <linux/pkt_sched.h> |
| #define __KERNEL_SYSCALLS__ |
| #include <linux/unistd.h> |
| #include <linux/vmalloc.h> |
| #include <linux/random.h> |
| #include <linux/string.h> |
| #include <linux/scatterlist.h> |
| #include "drbd_int.h" |
| #include "drbd_protocol.h" |
| #include "drbd_req.h" |
| #include "drbd_vli.h" |
| |
| #define PRO_FEATURES (FF_TRIM) |
| |
| struct packet_info { |
| enum drbd_packet cmd; |
| unsigned int size; |
| unsigned int vnr; |
| void *data; |
| }; |
| |
| enum finish_epoch { |
| FE_STILL_LIVE, |
| FE_DESTROYED, |
| FE_RECYCLED, |
| }; |
| |
| static int drbd_do_features(struct drbd_connection *connection); |
| static int drbd_do_auth(struct drbd_connection *connection); |
| static int drbd_disconnected(struct drbd_peer_device *); |
| static void conn_wait_active_ee_empty(struct drbd_connection *connection); |
| static enum finish_epoch drbd_may_finish_epoch(struct drbd_connection *, struct drbd_epoch *, enum epoch_event); |
| static int e_end_block(struct drbd_work *, int); |
| |
| |
| #define GFP_TRY (__GFP_HIGHMEM | __GFP_NOWARN) |
| |
| /* |
| * some helper functions to deal with single linked page lists, |
| * page->private being our "next" pointer. |
| */ |
| |
| /* If at least n pages are linked at head, get n pages off. |
| * Otherwise, don't modify head, and return NULL. |
| * Locking is the responsibility of the caller. |
| */ |
| static struct page *page_chain_del(struct page **head, int n) |
| { |
| struct page *page; |
| struct page *tmp; |
| |
| BUG_ON(!n); |
| BUG_ON(!head); |
| |
| page = *head; |
| |
| if (!page) |
| return NULL; |
| |
| while (page) { |
| tmp = page_chain_next(page); |
| if (--n == 0) |
| break; /* found sufficient pages */ |
| if (tmp == NULL) |
| /* insufficient pages, don't use any of them. */ |
| return NULL; |
| page = tmp; |
| } |
| |
| /* add end of list marker for the returned list */ |
| set_page_private(page, 0); |
| /* actual return value, and adjustment of head */ |
| page = *head; |
| *head = tmp; |
| return page; |
| } |
| |
| /* may be used outside of locks to find the tail of a (usually short) |
| * "private" page chain, before adding it back to a global chain head |
| * with page_chain_add() under a spinlock. */ |
| static struct page *page_chain_tail(struct page *page, int *len) |
| { |
| struct page *tmp; |
| int i = 1; |
| while ((tmp = page_chain_next(page))) |
| ++i, page = tmp; |
| if (len) |
| *len = i; |
| return page; |
| } |
| |
| static int page_chain_free(struct page *page) |
| { |
| struct page *tmp; |
| int i = 0; |
| page_chain_for_each_safe(page, tmp) { |
| put_page(page); |
| ++i; |
| } |
| return i; |
| } |
| |
| static void page_chain_add(struct page **head, |
| struct page *chain_first, struct page *chain_last) |
| { |
| #if 1 |
| struct page *tmp; |
| tmp = page_chain_tail(chain_first, NULL); |
| BUG_ON(tmp != chain_last); |
| #endif |
| |
| /* add chain to head */ |
| set_page_private(chain_last, (unsigned long)*head); |
| *head = chain_first; |
| } |
| |
| static struct page *__drbd_alloc_pages(struct drbd_device *device, |
| unsigned int number) |
| { |
| struct page *page = NULL; |
| struct page *tmp = NULL; |
| unsigned int i = 0; |
| |
| /* Yes, testing drbd_pp_vacant outside the lock is racy. |
| * So what. It saves a spin_lock. */ |
| if (drbd_pp_vacant >= number) { |
| spin_lock(&drbd_pp_lock); |
| page = page_chain_del(&drbd_pp_pool, number); |
| if (page) |
| drbd_pp_vacant -= number; |
| spin_unlock(&drbd_pp_lock); |
| if (page) |
| return page; |
| } |
| |
| /* GFP_TRY, because we must not cause arbitrary write-out: in a DRBD |
| * "criss-cross" setup, that might cause write-out on some other DRBD, |
| * which in turn might block on the other node at this very place. */ |
| for (i = 0; i < number; i++) { |
| tmp = alloc_page(GFP_TRY); |
| if (!tmp) |
| break; |
| set_page_private(tmp, (unsigned long)page); |
| page = tmp; |
| } |
| |
| if (i == number) |
| return page; |
| |
| /* Not enough pages immediately available this time. |
| * No need to jump around here, drbd_alloc_pages will retry this |
| * function "soon". */ |
| if (page) { |
| tmp = page_chain_tail(page, NULL); |
| spin_lock(&drbd_pp_lock); |
| page_chain_add(&drbd_pp_pool, page, tmp); |
| drbd_pp_vacant += i; |
| spin_unlock(&drbd_pp_lock); |
| } |
| return NULL; |
| } |
| |
| static void reclaim_finished_net_peer_reqs(struct drbd_device *device, |
| struct list_head *to_be_freed) |
| { |
| struct drbd_peer_request *peer_req, *tmp; |
| |
| /* The EEs are always appended to the end of the list. Since |
| they are sent in order over the wire, they have to finish |
| in order. As soon as we see the first not finished we can |
| stop to examine the list... */ |
| |
| list_for_each_entry_safe(peer_req, tmp, &device->net_ee, w.list) { |
| if (drbd_peer_req_has_active_page(peer_req)) |
| break; |
| list_move(&peer_req->w.list, to_be_freed); |
| } |
| } |
| |
| static void drbd_kick_lo_and_reclaim_net(struct drbd_device *device) |
| { |
| LIST_HEAD(reclaimed); |
| struct drbd_peer_request *peer_req, *t; |
| |
| spin_lock_irq(&device->resource->req_lock); |
| reclaim_finished_net_peer_reqs(device, &reclaimed); |
| spin_unlock_irq(&device->resource->req_lock); |
| |
| list_for_each_entry_safe(peer_req, t, &reclaimed, w.list) |
| drbd_free_net_peer_req(device, peer_req); |
| } |
| |
| /** |
| * drbd_alloc_pages() - Returns @number pages, retries forever (or until signalled) |
| * @device: DRBD device. |
| * @number: number of pages requested |
| * @retry: whether to retry, if not enough pages are available right now |
| * |
| * Tries to allocate number pages, first from our own page pool, then from |
| * the kernel. |
| * Possibly retry until DRBD frees sufficient pages somewhere else. |
| * |
| * If this allocation would exceed the max_buffers setting, we throttle |
| * allocation (schedule_timeout) to give the system some room to breathe. |
| * |
| * We do not use max-buffers as hard limit, because it could lead to |
| * congestion and further to a distributed deadlock during online-verify or |
| * (checksum based) resync, if the max-buffers, socket buffer sizes and |
| * resync-rate settings are mis-configured. |
| * |
| * Returns a page chain linked via page->private. |
| */ |
| struct page *drbd_alloc_pages(struct drbd_peer_device *peer_device, unsigned int number, |
| bool retry) |
| { |
| struct drbd_device *device = peer_device->device; |
| struct page *page = NULL; |
| struct net_conf *nc; |
| DEFINE_WAIT(wait); |
| unsigned int mxb; |
| |
| rcu_read_lock(); |
| nc = rcu_dereference(peer_device->connection->net_conf); |
| mxb = nc ? nc->max_buffers : 1000000; |
| rcu_read_unlock(); |
| |
| if (atomic_read(&device->pp_in_use) < mxb) |
| page = __drbd_alloc_pages(device, number); |
| |
| while (page == NULL) { |
| prepare_to_wait(&drbd_pp_wait, &wait, TASK_INTERRUPTIBLE); |
| |
| drbd_kick_lo_and_reclaim_net(device); |
| |
| if (atomic_read(&device->pp_in_use) < mxb) { |
| page = __drbd_alloc_pages(device, number); |
| if (page) |
| break; |
| } |
| |
| if (!retry) |
| break; |
| |
| if (signal_pending(current)) { |
| drbd_warn(device, "drbd_alloc_pages interrupted!\n"); |
| break; |
| } |
| |
| if (schedule_timeout(HZ/10) == 0) |
| mxb = UINT_MAX; |
| } |
| finish_wait(&drbd_pp_wait, &wait); |
| |
| if (page) |
| atomic_add(number, &device->pp_in_use); |
| return page; |
| } |
| |
| /* Must not be used from irq, as that may deadlock: see drbd_alloc_pages. |
| * Is also used from inside an other spin_lock_irq(&resource->req_lock); |
| * Either links the page chain back to the global pool, |
| * or returns all pages to the system. */ |
| static void drbd_free_pages(struct drbd_device *device, struct page *page, int is_net) |
| { |
| atomic_t *a = is_net ? &device->pp_in_use_by_net : &device->pp_in_use; |
| int i; |
| |
| if (page == NULL) |
| return; |
| |
| if (drbd_pp_vacant > (DRBD_MAX_BIO_SIZE/PAGE_SIZE) * minor_count) |
| i = page_chain_free(page); |
| else { |
| struct page *tmp; |
| tmp = page_chain_tail(page, &i); |
| spin_lock(&drbd_pp_lock); |
| page_chain_add(&drbd_pp_pool, page, tmp); |
| drbd_pp_vacant += i; |
| spin_unlock(&drbd_pp_lock); |
| } |
| i = atomic_sub_return(i, a); |
| if (i < 0) |
| drbd_warn(device, "ASSERTION FAILED: %s: %d < 0\n", |
| is_net ? "pp_in_use_by_net" : "pp_in_use", i); |
| wake_up(&drbd_pp_wait); |
| } |
| |
| /* |
| You need to hold the req_lock: |
| _drbd_wait_ee_list_empty() |
| |
| You must not have the req_lock: |
| drbd_free_peer_req() |
| drbd_alloc_peer_req() |
| drbd_free_peer_reqs() |
| drbd_ee_fix_bhs() |
| drbd_finish_peer_reqs() |
| drbd_clear_done_ee() |
| drbd_wait_ee_list_empty() |
| */ |
| |
| struct drbd_peer_request * |
| drbd_alloc_peer_req(struct drbd_peer_device *peer_device, u64 id, sector_t sector, |
| unsigned int data_size, bool has_payload, gfp_t gfp_mask) __must_hold(local) |
| { |
| struct drbd_device *device = peer_device->device; |
| struct drbd_peer_request *peer_req; |
| struct page *page = NULL; |
| unsigned nr_pages = (data_size + PAGE_SIZE -1) >> PAGE_SHIFT; |
| |
| if (drbd_insert_fault(device, DRBD_FAULT_AL_EE)) |
| return NULL; |
| |
| peer_req = mempool_alloc(drbd_ee_mempool, gfp_mask & ~__GFP_HIGHMEM); |
| if (!peer_req) { |
| if (!(gfp_mask & __GFP_NOWARN)) |
| drbd_err(device, "%s: allocation failed\n", __func__); |
| return NULL; |
| } |
| |
| if (has_payload && data_size) { |
| page = drbd_alloc_pages(peer_device, nr_pages, |
| gfpflags_allow_blocking(gfp_mask)); |
| if (!page) |
| goto fail; |
| } |
| |
| memset(peer_req, 0, sizeof(*peer_req)); |
| INIT_LIST_HEAD(&peer_req->w.list); |
| drbd_clear_interval(&peer_req->i); |
| peer_req->i.size = data_size; |
| peer_req->i.sector = sector; |
| peer_req->submit_jif = jiffies; |
| peer_req->peer_device = peer_device; |
| peer_req->pages = page; |
| /* |
| * The block_id is opaque to the receiver. It is not endianness |
| * converted, and sent back to the sender unchanged. |
| */ |
| peer_req->block_id = id; |
| |
| return peer_req; |
| |
| fail: |
| mempool_free(peer_req, drbd_ee_mempool); |
| return NULL; |
| } |
| |
| void __drbd_free_peer_req(struct drbd_device *device, struct drbd_peer_request *peer_req, |
| int is_net) |
| { |
| might_sleep(); |
| if (peer_req->flags & EE_HAS_DIGEST) |
| kfree(peer_req->digest); |
| drbd_free_pages(device, peer_req->pages, is_net); |
| D_ASSERT(device, atomic_read(&peer_req->pending_bios) == 0); |
| D_ASSERT(device, drbd_interval_empty(&peer_req->i)); |
| if (!expect(!(peer_req->flags & EE_CALL_AL_COMPLETE_IO))) { |
| peer_req->flags &= ~EE_CALL_AL_COMPLETE_IO; |
| drbd_al_complete_io(device, &peer_req->i); |
| } |
| mempool_free(peer_req, drbd_ee_mempool); |
| } |
| |
| int drbd_free_peer_reqs(struct drbd_device *device, struct list_head *list) |
| { |
| LIST_HEAD(work_list); |
| struct drbd_peer_request *peer_req, *t; |
| int count = 0; |
| int is_net = list == &device->net_ee; |
| |
| spin_lock_irq(&device->resource->req_lock); |
| list_splice_init(list, &work_list); |
| spin_unlock_irq(&device->resource->req_lock); |
| |
| list_for_each_entry_safe(peer_req, t, &work_list, w.list) { |
| __drbd_free_peer_req(device, peer_req, is_net); |
| count++; |
| } |
| return count; |
| } |
| |
| /* |
| * See also comments in _req_mod(,BARRIER_ACKED) and receive_Barrier. |
| */ |
| static int drbd_finish_peer_reqs(struct drbd_device *device) |
| { |
| LIST_HEAD(work_list); |
| LIST_HEAD(reclaimed); |
| struct drbd_peer_request *peer_req, *t; |
| int err = 0; |
| |
| spin_lock_irq(&device->resource->req_lock); |
| reclaim_finished_net_peer_reqs(device, &reclaimed); |
| list_splice_init(&device->done_ee, &work_list); |
| spin_unlock_irq(&device->resource->req_lock); |
| |
| list_for_each_entry_safe(peer_req, t, &reclaimed, w.list) |
| drbd_free_net_peer_req(device, peer_req); |
| |
| /* possible callbacks here: |
| * e_end_block, and e_end_resync_block, e_send_superseded. |
| * all ignore the last argument. |
| */ |
| list_for_each_entry_safe(peer_req, t, &work_list, w.list) { |
| int err2; |
| |
| /* list_del not necessary, next/prev members not touched */ |
| err2 = peer_req->w.cb(&peer_req->w, !!err); |
| if (!err) |
| err = err2; |
| drbd_free_peer_req(device, peer_req); |
| } |
| wake_up(&device->ee_wait); |
| |
| return err; |
| } |
| |
| static void _drbd_wait_ee_list_empty(struct drbd_device *device, |
| struct list_head *head) |
| { |
| DEFINE_WAIT(wait); |
| |
| /* avoids spin_lock/unlock |
| * and calling prepare_to_wait in the fast path */ |
| while (!list_empty(head)) { |
| prepare_to_wait(&device->ee_wait, &wait, TASK_UNINTERRUPTIBLE); |
| spin_unlock_irq(&device->resource->req_lock); |
| io_schedule(); |
| finish_wait(&device->ee_wait, &wait); |
| spin_lock_irq(&device->resource->req_lock); |
| } |
| } |
| |
| static void drbd_wait_ee_list_empty(struct drbd_device *device, |
| struct list_head *head) |
| { |
| spin_lock_irq(&device->resource->req_lock); |
| _drbd_wait_ee_list_empty(device, head); |
| spin_unlock_irq(&device->resource->req_lock); |
| } |
| |
| static int drbd_recv_short(struct socket *sock, void *buf, size_t size, int flags) |
| { |
| struct kvec iov = { |
| .iov_base = buf, |
| .iov_len = size, |
| }; |
| struct msghdr msg = { |
| .msg_flags = (flags ? flags : MSG_WAITALL | MSG_NOSIGNAL) |
| }; |
| return kernel_recvmsg(sock, &msg, &iov, 1, size, msg.msg_flags); |
| } |
| |
| static int drbd_recv(struct drbd_connection *connection, void *buf, size_t size) |
| { |
| int rv; |
| |
| rv = drbd_recv_short(connection->data.socket, buf, size, 0); |
| |
| if (rv < 0) { |
| if (rv == -ECONNRESET) |
| drbd_info(connection, "sock was reset by peer\n"); |
| else if (rv != -ERESTARTSYS) |
| drbd_err(connection, "sock_recvmsg returned %d\n", rv); |
| } else if (rv == 0) { |
| if (test_bit(DISCONNECT_SENT, &connection->flags)) { |
| long t; |
| rcu_read_lock(); |
| t = rcu_dereference(connection->net_conf)->ping_timeo * HZ/10; |
| rcu_read_unlock(); |
| |
| t = wait_event_timeout(connection->ping_wait, connection->cstate < C_WF_REPORT_PARAMS, t); |
| |
| if (t) |
| goto out; |
| } |
| drbd_info(connection, "sock was shut down by peer\n"); |
| } |
| |
| if (rv != size) |
| conn_request_state(connection, NS(conn, C_BROKEN_PIPE), CS_HARD); |
| |
| out: |
| return rv; |
| } |
| |
| static int drbd_recv_all(struct drbd_connection *connection, void *buf, size_t size) |
| { |
| int err; |
| |
| err = drbd_recv(connection, buf, size); |
| if (err != size) { |
| if (err >= 0) |
| err = -EIO; |
| } else |
| err = 0; |
| return err; |
| } |
| |
| static int drbd_recv_all_warn(struct drbd_connection *connection, void *buf, size_t size) |
| { |
| int err; |
| |
| err = drbd_recv_all(connection, buf, size); |
| if (err && !signal_pending(current)) |
| drbd_warn(connection, "short read (expected size %d)\n", (int)size); |
| return err; |
| } |
| |
| /* quoting tcp(7): |
| * On individual connections, the socket buffer size must be set prior to the |
| * listen(2) or connect(2) calls in order to have it take effect. |
| * This is our wrapper to do so. |
| */ |
| static void drbd_setbufsize(struct socket *sock, unsigned int snd, |
| unsigned int rcv) |
| { |
| /* open coded SO_SNDBUF, SO_RCVBUF */ |
| if (snd) { |
| sock->sk->sk_sndbuf = snd; |
| sock->sk->sk_userlocks |= SOCK_SNDBUF_LOCK; |
| } |
| if (rcv) { |
| sock->sk->sk_rcvbuf = rcv; |
| sock->sk->sk_userlocks |= SOCK_RCVBUF_LOCK; |
| } |
| } |
| |
| static struct socket *drbd_try_connect(struct drbd_connection *connection) |
| { |
| const char *what; |
| struct socket *sock; |
| struct sockaddr_in6 src_in6; |
| struct sockaddr_in6 peer_in6; |
| struct net_conf *nc; |
| int err, peer_addr_len, my_addr_len; |
| int sndbuf_size, rcvbuf_size, connect_int; |
| int disconnect_on_error = 1; |
| |
| rcu_read_lock(); |
| nc = rcu_dereference(connection->net_conf); |
| if (!nc) { |
| rcu_read_unlock(); |
| return NULL; |
| } |
| sndbuf_size = nc->sndbuf_size; |
| rcvbuf_size = nc->rcvbuf_size; |
| connect_int = nc->connect_int; |
| rcu_read_unlock(); |
| |
| my_addr_len = min_t(int, connection->my_addr_len, sizeof(src_in6)); |
| memcpy(&src_in6, &connection->my_addr, my_addr_len); |
| |
| if (((struct sockaddr *)&connection->my_addr)->sa_family == AF_INET6) |
| src_in6.sin6_port = 0; |
| else |
| ((struct sockaddr_in *)&src_in6)->sin_port = 0; /* AF_INET & AF_SCI */ |
| |
| peer_addr_len = min_t(int, connection->peer_addr_len, sizeof(src_in6)); |
| memcpy(&peer_in6, &connection->peer_addr, peer_addr_len); |
| |
| what = "sock_create_kern"; |
| err = sock_create_kern(&init_net, ((struct sockaddr *)&src_in6)->sa_family, |
| SOCK_STREAM, IPPROTO_TCP, &sock); |
| if (err < 0) { |
| sock = NULL; |
| goto out; |
| } |
| |
| sock->sk->sk_rcvtimeo = |
| sock->sk->sk_sndtimeo = connect_int * HZ; |
| drbd_setbufsize(sock, sndbuf_size, rcvbuf_size); |
| |
| /* explicitly bind to the configured IP as source IP |
| * for the outgoing connections. |
| * This is needed for multihomed hosts and to be |
| * able to use lo: interfaces for drbd. |
| * Make sure to use 0 as port number, so linux selects |
| * a free one dynamically. |
| */ |
| what = "bind before connect"; |
| err = sock->ops->bind(sock, (struct sockaddr *) &src_in6, my_addr_len); |
| if (err < 0) |
| goto out; |
| |
| /* connect may fail, peer not yet available. |
| * stay C_WF_CONNECTION, don't go Disconnecting! */ |
| disconnect_on_error = 0; |
| what = "connect"; |
| err = sock->ops->connect(sock, (struct sockaddr *) &peer_in6, peer_addr_len, 0); |
| |
| out: |
| if (err < 0) { |
| if (sock) { |
| sock_release(sock); |
| sock = NULL; |
| } |
| switch (-err) { |
| /* timeout, busy, signal pending */ |
| case ETIMEDOUT: case EAGAIN: case EINPROGRESS: |
| case EINTR: case ERESTARTSYS: |
| /* peer not (yet) available, network problem */ |
| case ECONNREFUSED: case ENETUNREACH: |
| case EHOSTDOWN: case EHOSTUNREACH: |
| disconnect_on_error = 0; |
| break; |
| default: |
| drbd_err(connection, "%s failed, err = %d\n", what, err); |
| } |
| if (disconnect_on_error) |
| conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_HARD); |
| } |
| |
| return sock; |
| } |
| |
| struct accept_wait_data { |
| struct drbd_connection *connection; |
| struct socket *s_listen; |
| struct completion door_bell; |
| void (*original_sk_state_change)(struct sock *sk); |
| |
| }; |
| |
| static void drbd_incoming_connection(struct sock *sk) |
| { |
| struct accept_wait_data *ad = sk->sk_user_data; |
| void (*state_change)(struct sock *sk); |
| |
| state_change = ad->original_sk_state_change; |
| if (sk->sk_state == TCP_ESTABLISHED) |
| complete(&ad->door_bell); |
| state_change(sk); |
| } |
| |
| static int prepare_listen_socket(struct drbd_connection *connection, struct accept_wait_data *ad) |
| { |
| int err, sndbuf_size, rcvbuf_size, my_addr_len; |
| struct sockaddr_in6 my_addr; |
| struct socket *s_listen; |
| struct net_conf *nc; |
| const char *what; |
| |
| rcu_read_lock(); |
| nc = rcu_dereference(connection->net_conf); |
| if (!nc) { |
| rcu_read_unlock(); |
| return -EIO; |
| } |
| sndbuf_size = nc->sndbuf_size; |
| rcvbuf_size = nc->rcvbuf_size; |
| rcu_read_unlock(); |
| |
| my_addr_len = min_t(int, connection->my_addr_len, sizeof(struct sockaddr_in6)); |
| memcpy(&my_addr, &connection->my_addr, my_addr_len); |
| |
| what = "sock_create_kern"; |
| err = sock_create_kern(&init_net, ((struct sockaddr *)&my_addr)->sa_family, |
| SOCK_STREAM, IPPROTO_TCP, &s_listen); |
| if (err) { |
| s_listen = NULL; |
| goto out; |
| } |
| |
| s_listen->sk->sk_reuse = SK_CAN_REUSE; /* SO_REUSEADDR */ |
| drbd_setbufsize(s_listen, sndbuf_size, rcvbuf_size); |
| |
| what = "bind before listen"; |
| err = s_listen->ops->bind(s_listen, (struct sockaddr *)&my_addr, my_addr_len); |
| if (err < 0) |
| goto out; |
| |
| ad->s_listen = s_listen; |
| write_lock_bh(&s_listen->sk->sk_callback_lock); |
| ad->original_sk_state_change = s_listen->sk->sk_state_change; |
| s_listen->sk->sk_state_change = drbd_incoming_connection; |
| s_listen->sk->sk_user_data = ad; |
| write_unlock_bh(&s_listen->sk->sk_callback_lock); |
| |
| what = "listen"; |
| err = s_listen->ops->listen(s_listen, 5); |
| if (err < 0) |
| goto out; |
| |
| return 0; |
| out: |
| if (s_listen) |
| sock_release(s_listen); |
| if (err < 0) { |
| if (err != -EAGAIN && err != -EINTR && err != -ERESTARTSYS) { |
| drbd_err(connection, "%s failed, err = %d\n", what, err); |
| conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_HARD); |
| } |
| } |
| |
| return -EIO; |
| } |
| |
| static void unregister_state_change(struct sock *sk, struct accept_wait_data *ad) |
| { |
| write_lock_bh(&sk->sk_callback_lock); |
| sk->sk_state_change = ad->original_sk_state_change; |
| sk->sk_user_data = NULL; |
| write_unlock_bh(&sk->sk_callback_lock); |
| } |
| |
| static struct socket *drbd_wait_for_connect(struct drbd_connection *connection, struct accept_wait_data *ad) |
| { |
| int timeo, connect_int, err = 0; |
| struct socket *s_estab = NULL; |
| struct net_conf *nc; |
| |
| rcu_read_lock(); |
| nc = rcu_dereference(connection->net_conf); |
| if (!nc) { |
| rcu_read_unlock(); |
| return NULL; |
| } |
| connect_int = nc->connect_int; |
| rcu_read_unlock(); |
| |
| timeo = connect_int * HZ; |
| /* 28.5% random jitter */ |
| timeo += (prandom_u32() & 1) ? timeo / 7 : -timeo / 7; |
| |
| err = wait_for_completion_interruptible_timeout(&ad->door_bell, timeo); |
| if (err <= 0) |
| return NULL; |
| |
| err = kernel_accept(ad->s_listen, &s_estab, 0); |
| if (err < 0) { |
| if (err != -EAGAIN && err != -EINTR && err != -ERESTARTSYS) { |
| drbd_err(connection, "accept failed, err = %d\n", err); |
| conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_HARD); |
| } |
| } |
| |
| if (s_estab) |
| unregister_state_change(s_estab->sk, ad); |
| |
| return s_estab; |
| } |
| |
| static int decode_header(struct drbd_connection *, void *, struct packet_info *); |
| |
| static int send_first_packet(struct drbd_connection *connection, struct drbd_socket *sock, |
| enum drbd_packet cmd) |
| { |
| if (!conn_prepare_command(connection, sock)) |
| return -EIO; |
| return conn_send_command(connection, sock, cmd, 0, NULL, 0); |
| } |
| |
| static int receive_first_packet(struct drbd_connection *connection, struct socket *sock) |
| { |
| unsigned int header_size = drbd_header_size(connection); |
| struct packet_info pi; |
| struct net_conf *nc; |
| int err; |
| |
| rcu_read_lock(); |
| nc = rcu_dereference(connection->net_conf); |
| if (!nc) { |
| rcu_read_unlock(); |
| return -EIO; |
| } |
| sock->sk->sk_rcvtimeo = nc->ping_timeo * 4 * HZ / 10; |
| rcu_read_unlock(); |
| |
| err = drbd_recv_short(sock, connection->data.rbuf, header_size, 0); |
| if (err != header_size) { |
| if (err >= 0) |
| err = -EIO; |
| return err; |
| } |
| err = decode_header(connection, connection->data.rbuf, &pi); |
| if (err) |
| return err; |
| return pi.cmd; |
| } |
| |
| /** |
| * drbd_socket_okay() - Free the socket if its connection is not okay |
| * @sock: pointer to the pointer to the socket. |
| */ |
| static bool drbd_socket_okay(struct socket **sock) |
| { |
| int rr; |
| char tb[4]; |
| |
| if (!*sock) |
| return false; |
| |
| rr = drbd_recv_short(*sock, tb, 4, MSG_DONTWAIT | MSG_PEEK); |
| |
| if (rr > 0 || rr == -EAGAIN) { |
| return true; |
| } else { |
| sock_release(*sock); |
| *sock = NULL; |
| return false; |
| } |
| } |
| |
| static bool connection_established(struct drbd_connection *connection, |
| struct socket **sock1, |
| struct socket **sock2) |
| { |
| struct net_conf *nc; |
| int timeout; |
| bool ok; |
| |
| if (!*sock1 || !*sock2) |
| return false; |
| |
| rcu_read_lock(); |
| nc = rcu_dereference(connection->net_conf); |
| timeout = (nc->sock_check_timeo ?: nc->ping_timeo) * HZ / 10; |
| rcu_read_unlock(); |
| schedule_timeout_interruptible(timeout); |
| |
| ok = drbd_socket_okay(sock1); |
| ok = drbd_socket_okay(sock2) && ok; |
| |
| return ok; |
| } |
| |
| /* Gets called if a connection is established, or if a new minor gets created |
| in a connection */ |
| int drbd_connected(struct drbd_peer_device *peer_device) |
| { |
| struct drbd_device *device = peer_device->device; |
| int err; |
| |
| atomic_set(&device->packet_seq, 0); |
| device->peer_seq = 0; |
| |
| device->state_mutex = peer_device->connection->agreed_pro_version < 100 ? |
| &peer_device->connection->cstate_mutex : |
| &device->own_state_mutex; |
| |
| err = drbd_send_sync_param(peer_device); |
| if (!err) |
| err = drbd_send_sizes(peer_device, 0, 0); |
| if (!err) |
| err = drbd_send_uuids(peer_device); |
| if (!err) |
| err = drbd_send_current_state(peer_device); |
| clear_bit(USE_DEGR_WFC_T, &device->flags); |
| clear_bit(RESIZE_PENDING, &device->flags); |
| atomic_set(&device->ap_in_flight, 0); |
| mod_timer(&device->request_timer, jiffies + HZ); /* just start it here. */ |
| return err; |
| } |
| |
| /* |
| * return values: |
| * 1 yes, we have a valid connection |
| * 0 oops, did not work out, please try again |
| * -1 peer talks different language, |
| * no point in trying again, please go standalone. |
| * -2 We do not have a network config... |
| */ |
| static int conn_connect(struct drbd_connection *connection) |
| { |
| struct drbd_socket sock, msock; |
| struct drbd_peer_device *peer_device; |
| struct net_conf *nc; |
| int vnr, timeout, h; |
| bool discard_my_data, ok; |
| enum drbd_state_rv rv; |
| struct accept_wait_data ad = { |
| .connection = connection, |
| .door_bell = COMPLETION_INITIALIZER_ONSTACK(ad.door_bell), |
| }; |
| |
| clear_bit(DISCONNECT_SENT, &connection->flags); |
| if (conn_request_state(connection, NS(conn, C_WF_CONNECTION), CS_VERBOSE) < SS_SUCCESS) |
| return -2; |
| |
| mutex_init(&sock.mutex); |
| sock.sbuf = connection->data.sbuf; |
| sock.rbuf = connection->data.rbuf; |
| sock.socket = NULL; |
| mutex_init(&msock.mutex); |
| msock.sbuf = connection->meta.sbuf; |
| msock.rbuf = connection->meta.rbuf; |
| msock.socket = NULL; |
| |
| /* Assume that the peer only understands protocol 80 until we know better. */ |
| connection->agreed_pro_version = 80; |
| |
| if (prepare_listen_socket(connection, &ad)) |
| return 0; |
| |
| do { |
| struct socket *s; |
| |
| s = drbd_try_connect(connection); |
| if (s) { |
| if (!sock.socket) { |
| sock.socket = s; |
| send_first_packet(connection, &sock, P_INITIAL_DATA); |
| } else if (!msock.socket) { |
| clear_bit(RESOLVE_CONFLICTS, &connection->flags); |
| msock.socket = s; |
| send_first_packet(connection, &msock, P_INITIAL_META); |
| } else { |
| drbd_err(connection, "Logic error in conn_connect()\n"); |
| goto out_release_sockets; |
| } |
| } |
| |
| if (connection_established(connection, &sock.socket, &msock.socket)) |
| break; |
| |
| retry: |
| s = drbd_wait_for_connect(connection, &ad); |
| if (s) { |
| int fp = receive_first_packet(connection, s); |
| drbd_socket_okay(&sock.socket); |
| drbd_socket_okay(&msock.socket); |
| switch (fp) { |
| case P_INITIAL_DATA: |
| if (sock.socket) { |
| drbd_warn(connection, "initial packet S crossed\n"); |
| sock_release(sock.socket); |
| sock.socket = s; |
| goto randomize; |
| } |
| sock.socket = s; |
| break; |
| case P_INITIAL_META: |
| set_bit(RESOLVE_CONFLICTS, &connection->flags); |
| if (msock.socket) { |
| drbd_warn(connection, "initial packet M crossed\n"); |
| sock_release(msock.socket); |
| msock.socket = s; |
| goto randomize; |
| } |
| msock.socket = s; |
| break; |
| default: |
| drbd_warn(connection, "Error receiving initial packet\n"); |
| sock_release(s); |
| randomize: |
| if (prandom_u32() & 1) |
| goto retry; |
| } |
| } |
| |
| if (connection->cstate <= C_DISCONNECTING) |
| goto out_release_sockets; |
| if (signal_pending(current)) { |
| flush_signals(current); |
| smp_rmb(); |
| if (get_t_state(&connection->receiver) == EXITING) |
| goto out_release_sockets; |
| } |
| |
| ok = connection_established(connection, &sock.socket, &msock.socket); |
| } while (!ok); |
| |
| if (ad.s_listen) |
| sock_release(ad.s_listen); |
| |
| sock.socket->sk->sk_reuse = SK_CAN_REUSE; /* SO_REUSEADDR */ |
| msock.socket->sk->sk_reuse = SK_CAN_REUSE; /* SO_REUSEADDR */ |
| |
| sock.socket->sk->sk_allocation = GFP_NOIO; |
| msock.socket->sk->sk_allocation = GFP_NOIO; |
| |
| sock.socket->sk->sk_priority = TC_PRIO_INTERACTIVE_BULK; |
| msock.socket->sk->sk_priority = TC_PRIO_INTERACTIVE; |
| |
| /* NOT YET ... |
| * sock.socket->sk->sk_sndtimeo = connection->net_conf->timeout*HZ/10; |
| * sock.socket->sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; |
| * first set it to the P_CONNECTION_FEATURES timeout, |
| * which we set to 4x the configured ping_timeout. */ |
| rcu_read_lock(); |
| nc = rcu_dereference(connection->net_conf); |
| |
| sock.socket->sk->sk_sndtimeo = |
| sock.socket->sk->sk_rcvtimeo = nc->ping_timeo*4*HZ/10; |
| |
| msock.socket->sk->sk_rcvtimeo = nc->ping_int*HZ; |
| timeout = nc->timeout * HZ / 10; |
| discard_my_data = nc->discard_my_data; |
| rcu_read_unlock(); |
| |
| msock.socket->sk->sk_sndtimeo = timeout; |
| |
| /* we don't want delays. |
| * we use TCP_CORK where appropriate, though */ |
| drbd_tcp_nodelay(sock.socket); |
| drbd_tcp_nodelay(msock.socket); |
| |
| connection->data.socket = sock.socket; |
| connection->meta.socket = msock.socket; |
| connection->last_received = jiffies; |
| |
| h = drbd_do_features(connection); |
| if (h <= 0) |
| return h; |
| |
| if (connection->cram_hmac_tfm) { |
| /* drbd_request_state(device, NS(conn, WFAuth)); */ |
| switch (drbd_do_auth(connection)) { |
| case -1: |
| drbd_err(connection, "Authentication of peer failed\n"); |
| return -1; |
| case 0: |
| drbd_err(connection, "Authentication of peer failed, trying again.\n"); |
| return 0; |
| } |
| } |
| |
| connection->data.socket->sk->sk_sndtimeo = timeout; |
| connection->data.socket->sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; |
| |
| if (drbd_send_protocol(connection) == -EOPNOTSUPP) |
| return -1; |
| |
| /* Prevent a race between resync-handshake and |
| * being promoted to Primary. |
| * |
| * Grab and release the state mutex, so we know that any current |
| * drbd_set_role() is finished, and any incoming drbd_set_role |
| * will see the STATE_SENT flag, and wait for it to be cleared. |
| */ |
| idr_for_each_entry(&connection->peer_devices, peer_device, vnr) |
| mutex_lock(peer_device->device->state_mutex); |
| |
| set_bit(STATE_SENT, &connection->flags); |
| |
| idr_for_each_entry(&connection->peer_devices, peer_device, vnr) |
| mutex_unlock(peer_device->device->state_mutex); |
| |
| 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(); |
| |
| if (discard_my_data) |
| set_bit(DISCARD_MY_DATA, &device->flags); |
| else |
| clear_bit(DISCARD_MY_DATA, &device->flags); |
| |
| drbd_connected(peer_device); |
| kref_put(&device->kref, drbd_destroy_device); |
| rcu_read_lock(); |
| } |
| rcu_read_unlock(); |
| |
| rv = conn_request_state(connection, NS(conn, C_WF_REPORT_PARAMS), CS_VERBOSE); |
| if (rv < SS_SUCCESS || connection->cstate != C_WF_REPORT_PARAMS) { |
| clear_bit(STATE_SENT, &connection->flags); |
| return 0; |
| } |
| |
| drbd_thread_start(&connection->asender); |
| |
| mutex_lock(&connection->resource->conf_update); |
| /* The discard_my_data flag is a single-shot modifier to the next |
| * connection attempt, the handshake of which is now well underway. |
| * No need for rcu style copying of the whole struct |
| * just to clear a single value. */ |
| connection->net_conf->discard_my_data = 0; |
| mutex_unlock(&connection->resource->conf_update); |
| |
| return h; |
| |
| out_release_sockets: |
| if (ad.s_listen) |
| sock_release(ad.s_listen); |
| if (sock.socket) |
| sock_release(sock.socket); |
| if (msock.socket) |
| sock_release(msock.socket); |
| return -1; |
| } |
| |
| static int decode_header(struct drbd_connection *connection, void *header, struct packet_info *pi) |
| { |
| unsigned int header_size = drbd_header_size(connection); |
| |
| if (header_size == sizeof(struct p_header100) && |
| *(__be32 *)header == cpu_to_be32(DRBD_MAGIC_100)) { |
| struct p_header100 *h = header; |
| if (h->pad != 0) { |
| drbd_err(connection, "Header padding is not zero\n"); |
| return -EINVAL; |
| } |
| pi->vnr = be16_to_cpu(h->volume); |
| pi->cmd = be16_to_cpu(h->command); |
| pi->size = be32_to_cpu(h->length); |
| } else if (header_size == sizeof(struct p_header95) && |
| *(__be16 *)header == cpu_to_be16(DRBD_MAGIC_BIG)) { |
| struct p_header95 *h = header; |
| pi->cmd = be16_to_cpu(h->command); |
| pi->size = be32_to_cpu(h->length); |
| pi->vnr = 0; |
| } else if (header_size == sizeof(struct p_header80) && |
| *(__be32 *)header == cpu_to_be32(DRBD_MAGIC)) { |
| struct p_header80 *h = header; |
| pi->cmd = be16_to_cpu(h->command); |
| pi->size = be16_to_cpu(h->length); |
| pi->vnr = 0; |
| } else { |
| drbd_err(connection, "Wrong magic value 0x%08x in protocol version %d\n", |
| be32_to_cpu(*(__be32 *)header), |
| connection->agreed_pro_version); |
| return -EINVAL; |
| } |
| pi->data = header + header_size; |
| return 0; |
| } |
| |
| static int drbd_recv_header(struct drbd_connection *connection, struct packet_info *pi) |
| { |
| void *buffer = connection->data.rbuf; |
| int err; |
| |
| err = drbd_recv_all_warn(connection, buffer, drbd_header_size(connection)); |
| if (err) |
| return err; |
| |
| err = decode_header(connection, buffer, pi); |
| connection->last_received = jiffies; |
| |
| return err; |
| } |
| |
| static void drbd_flush(struct drbd_connection *connection) |
| { |
| int rv; |
| struct drbd_peer_device *peer_device; |
| int vnr; |
| |
| if (connection->resource->write_ordering >= WO_bdev_flush) { |
| rcu_read_lock(); |
| idr_for_each_entry(&connection->peer_devices, peer_device, vnr) { |
| struct drbd_device *device = peer_device->device; |
| |
| if (!get_ldev(device)) |
| continue; |
| kref_get(&device->kref); |
| rcu_read_unlock(); |
| |
| /* Right now, we have only this one synchronous code path |
| * for flushes between request epochs. |
| * We may want to make those asynchronous, |
| * or at least parallelize the flushes to the volume devices. |
| */ |
| device->flush_jif = jiffies; |
| set_bit(FLUSH_PENDING, &device->flags); |
| rv = blkdev_issue_flush(device->ldev->backing_bdev, |
| GFP_NOIO, NULL); |
| clear_bit(FLUSH_PENDING, &device->flags); |
| if (rv) { |
| drbd_info(device, "local disk flush failed with status %d\n", rv); |
| /* would rather check on EOPNOTSUPP, but that is not reliable. |
| * don't try again for ANY return value != 0 |
| * if (rv == -EOPNOTSUPP) */ |
| drbd_bump_write_ordering(connection->resource, NULL, WO_drain_io); |
| } |
| put_ldev(device); |
| kref_put(&device->kref, drbd_destroy_device); |
| |
| rcu_read_lock(); |
| if (rv) |
| break; |
| } |
| rcu_read_unlock(); |
| } |
| } |
| |
| /** |
| * drbd_may_finish_epoch() - Applies an epoch_event to the epoch's state, eventually finishes it. |
| * @device: DRBD device. |
| * @epoch: Epoch object. |
| * @ev: Epoch event. |
| */ |
| static enum finish_epoch drbd_may_finish_epoch(struct drbd_connection *connection, |
| struct drbd_epoch *epoch, |
| enum epoch_event ev) |
| { |
| int epoch_size; |
| struct drbd_epoch *next_epoch; |
| enum finish_epoch rv = FE_STILL_LIVE; |
| |
| spin_lock(&connection->epoch_lock); |
| do { |
| next_epoch = NULL; |
| |
| epoch_size = atomic_read(&epoch->epoch_size); |
| |
| switch (ev & ~EV_CLEANUP) { |
| case EV_PUT: |
| atomic_dec(&epoch->active); |
| break; |
| case EV_GOT_BARRIER_NR: |
| set_bit(DE_HAVE_BARRIER_NUMBER, &epoch->flags); |
| break; |
| case EV_BECAME_LAST: |
| /* nothing to do*/ |
| break; |
| } |
| |
| if (epoch_size != 0 && |
| atomic_read(&epoch->active) == 0 && |
| (test_bit(DE_HAVE_BARRIER_NUMBER, &epoch->flags) || ev & EV_CLEANUP)) { |
| if (!(ev & EV_CLEANUP)) { |
| spin_unlock(&connection->epoch_lock); |
| drbd_send_b_ack(epoch->connection, epoch->barrier_nr, epoch_size); |
| spin_lock(&connection->epoch_lock); |
| } |
| #if 0 |
| /* FIXME: dec unacked on connection, once we have |
| * something to count pending connection packets in. */ |
| if (test_bit(DE_HAVE_BARRIER_NUMBER, &epoch->flags)) |
| dec_unacked(epoch->connection); |
| #endif |
| |
| if (connection->current_epoch != epoch) { |
| next_epoch = list_entry(epoch->list.next, struct drbd_epoch, list); |
| list_del(&epoch->list); |
| ev = EV_BECAME_LAST | (ev & EV_CLEANUP); |
| connection->epochs--; |
| kfree(epoch); |
| |
| if (rv == FE_STILL_LIVE) |
| rv = FE_DESTROYED; |
| } else { |
| epoch->flags = 0; |
| atomic_set(&epoch->epoch_size, 0); |
| /* atomic_set(&epoch->active, 0); is already zero */ |
| if (rv == FE_STILL_LIVE) |
| rv = FE_RECYCLED; |
| } |
| } |
| |
| if (!next_epoch) |
| break; |
| |
| epoch = next_epoch; |
| } while (1); |
| |
| spin_unlock(&connection->epoch_lock); |
| |
| return rv; |
| } |
| |
| static enum write_ordering_e |
| max_allowed_wo(struct drbd_backing_dev *bdev, enum write_ordering_e wo) |
| { |
| struct disk_conf *dc; |
| |
| dc = rcu_dereference(bdev->disk_conf); |
| |
| if (wo == WO_bdev_flush && !dc->disk_flushes) |
| wo = WO_drain_io; |
| if (wo == WO_drain_io && !dc->disk_drain) |
| wo = WO_none; |
| |
| return wo; |
| } |
| |
| /** |
| * drbd_bump_write_ordering() - Fall back to an other write ordering method |
| * @connection: DRBD connection. |
| * @wo: Write ordering method to try. |
| */ |
| void drbd_bump_write_ordering(struct drbd_resource *resource, struct drbd_backing_dev *bdev, |
| enum write_ordering_e wo) |
| { |
| struct drbd_device *device; |
| enum write_ordering_e pwo; |
| int vnr; |
| static char *write_ordering_str[] = { |
| [WO_none] = "none", |
| [WO_drain_io] = "drain", |
| [WO_bdev_flush] = "flush", |
| }; |
| |
| pwo = resource->write_ordering; |
| if (wo != WO_bdev_flush) |
| wo = min(pwo, wo); |
| rcu_read_lock(); |
| idr_for_each_entry(&resource->devices, device, vnr) { |
| if (get_ldev(device)) { |
| wo = max_allowed_wo(device->ldev, wo); |
| if (device->ldev == bdev) |
| bdev = NULL; |
| put_ldev(device); |
| } |
| } |
| |
| if (bdev) |
| wo = max_allowed_wo(bdev, wo); |
| |
| rcu_read_unlock(); |
| |
| resource->write_ordering = wo; |
| if (pwo != resource->write_ordering || wo == WO_bdev_flush) |
| drbd_info(resource, "Method to ensure write ordering: %s\n", write_ordering_str[resource->write_ordering]); |
| } |
| |
| /** |
| * drbd_submit_peer_request() |
| * @device: DRBD device. |
| * @peer_req: peer request |
| * @rw: flag field, see bio->bi_rw |
| * |
| * May spread the pages to multiple bios, |
| * depending on bio_add_page restrictions. |
| * |
| * Returns 0 if all bios have been submitted, |
| * -ENOMEM if we could not allocate enough bios, |
| * -ENOSPC (any better suggestion?) if we have not been able to bio_add_page a |
| * single page to an empty bio (which should never happen and likely indicates |
| * that the lower level IO stack is in some way broken). This has been observed |
| * on certain Xen deployments. |
| */ |
| /* TODO allocate from our own bio_set. */ |
| int drbd_submit_peer_request(struct drbd_device *device, |
| struct drbd_peer_request *peer_req, |
| const unsigned rw, const int fault_type) |
| { |
| struct bio *bios = NULL; |
| struct bio *bio; |
| struct page *page = peer_req->pages; |
| sector_t sector = peer_req->i.sector; |
| unsigned data_size = peer_req->i.size; |
| unsigned n_bios = 0; |
| unsigned nr_pages = (data_size + PAGE_SIZE -1) >> PAGE_SHIFT; |
| int err = -ENOMEM; |
| |
| if (peer_req->flags & EE_IS_TRIM_USE_ZEROOUT) { |
| /* wait for all pending IO completions, before we start |
| * zeroing things out. */ |
| conn_wait_active_ee_empty(first_peer_device(device)->connection); |
| /* add it to the active list now, |
| * so we can find it to present it in debugfs */ |
| peer_req->submit_jif = jiffies; |
| peer_req->flags |= EE_SUBMITTED; |
| spin_lock_irq(&device->resource->req_lock); |
| list_add_tail(&peer_req->w.list, &device->active_ee); |
| spin_unlock_irq(&device->resource->req_lock); |
| if (blkdev_issue_zeroout(device->ldev->backing_bdev, |
| sector, data_size >> 9, GFP_NOIO, false)) |
| peer_req->flags |= EE_WAS_ERROR; |
| drbd_endio_write_sec_final(peer_req); |
| return 0; |
| } |
| |
| /* Discards don't have any payload. |
| * But the scsi layer still expects a bio_vec it can use internally, |
| * see sd_setup_discard_cmnd() and blk_add_request_payload(). */ |
| if (peer_req->flags & EE_IS_TRIM) |
| nr_pages = 1; |
| |
| /* In most cases, we will only need one bio. But in case the lower |
| * level restrictions happen to be different at this offset on this |
| * side than those of the sending peer, we may need to submit the |
| * request in more than one bio. |
| * |
| * Plain bio_alloc is good enough here, this is no DRBD internally |
| * generated bio, but a bio allocated on behalf of the peer. |
| */ |
| next_bio: |
| bio = bio_alloc(GFP_NOIO, nr_pages); |
| if (!bio) { |
| drbd_err(device, "submit_ee: Allocation of a bio failed (nr_pages=%u)\n", nr_pages); |
| goto fail; |
| } |
| /* > peer_req->i.sector, unless this is the first bio */ |
| bio->bi_iter.bi_sector = sector; |
| bio->bi_bdev = device->ldev->backing_bdev; |
| bio->bi_rw = rw; |
| bio->bi_private = peer_req; |
| bio->bi_end_io = drbd_peer_request_endio; |
| |
| bio->bi_next = bios; |
| bios = bio; |
| ++n_bios; |
| |
| if (rw & REQ_DISCARD) { |
| bio->bi_iter.bi_size = data_size; |
| goto submit; |
| } |
| |
| page_chain_for_each(page) { |
| unsigned len = min_t(unsigned, data_size, PAGE_SIZE); |
| if (!bio_add_page(bio, page, len, 0)) { |
| /* A single page must always be possible! |
| * But in case it fails anyways, |
| * we deal with it, and complain (below). */ |
| if (bio->bi_vcnt == 0) { |
| drbd_err(device, |
| "bio_add_page failed for len=%u, " |
| "bi_vcnt=0 (bi_sector=%llu)\n", |
| len, (uint64_t)bio->bi_iter.bi_sector); |
| err = -ENOSPC; |
| goto fail; |
| } |
| goto next_bio; |
| } |
| data_size -= len; |
| sector += len >> 9; |
| --nr_pages; |
| } |
| D_ASSERT(device, data_size == 0); |
| submit: |
| D_ASSERT(device, page == NULL); |
| |
| atomic_set(&peer_req->pending_bios, n_bios); |
| /* for debugfs: update timestamp, mark as submitted */ |
| peer_req->submit_jif = jiffies; |
| peer_req->flags |= EE_SUBMITTED; |
| do { |
| bio = bios; |
| bios = bios->bi_next; |
| bio->bi_next = NULL; |
| |
| drbd_generic_make_request(device, fault_type, bio); |
| } while (bios); |
| return 0; |
| |
| fail: |
| while (bios) { |
| bio = bios; |
| bios = bios->bi_next; |
| bio_put(bio); |
| } |
| return err; |
| } |
| |
| static void drbd_remove_epoch_entry_interval(struct drbd_device *device, |
| struct drbd_peer_request *peer_req) |
| { |
| struct drbd_interval *i = &peer_req->i; |
| |
| drbd_remove_interval(&device->write_requests, i); |
| drbd_clear_interval(i); |
| |
| /* Wake up any processes waiting for this peer request to complete. */ |
| if (i->waiting) |
| wake_up(&device->misc_wait); |
| } |
| |
| static void conn_wait_active_ee_empty(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_wait_ee_list_empty(device, &device->active_ee); |
| kref_put(&device->kref, drbd_destroy_device); |
| rcu_read_lock(); |
| } |
| rcu_read_unlock(); |
| } |
| |
| static struct drbd_peer_device * |
| conn_peer_device(struct drbd_connection *connection, int volume_number) |
| { |
| return idr_find(&connection->peer_devices, volume_number); |
| } |
| |
| static int receive_Barrier(struct drbd_connection *connection, struct packet_info *pi) |
| { |
| int rv; |
| struct p_barrier *p = pi->data; |
| struct drbd_epoch *epoch; |
| |
| /* FIXME these are unacked on connection, |
| * not a specific (peer)device. |
| */ |
| connection->current_epoch->barrier_nr = p->barrier; |
| connection->current_epoch->connection = connection; |
| rv = drbd_may_finish_epoch(connection, connection->current_epoch, EV_GOT_BARRIER_NR); |
| |
| /* P_BARRIER_ACK may imply that the corresponding extent is dropped from |
| * the activity log, which means it would not be resynced in case the |
| * R_PRIMARY crashes now. |
| * Therefore we must send the barrier_ack after the barrier request was |
| * completed. */ |
| switch (connection->resource->write_ordering) { |
| case WO_none: |
| if (rv == FE_RECYCLED) |
| return 0; |
| |
| /* receiver context, in the writeout path of the other node. |
| * avoid potential distributed deadlock */ |
| epoch = kmalloc(sizeof(struct drbd_epoch), GFP_NOIO); |
| if (epoch) |
| break; |
| else |
| drbd_warn(connection, "Allocation of an epoch failed, slowing down\n"); |
| /* Fall through */ |
| |
| case WO_bdev_flush: |
| case WO_drain_io: |
| conn_wait_active_ee_empty(connection); |
| drbd_flush(connection); |
| |
| if (atomic_read(&connection->current_epoch->epoch_size)) { |
| epoch = kmalloc(sizeof(struct drbd_epoch), GFP_NOIO); |
| if (epoch) |
| break; |
| } |
| |
| return 0; |
| default: |
| drbd_err(connection, "Strangeness in connection->write_ordering %d\n", |
| connection->resource->write_ordering); |
| return -EIO; |
| } |
| |
| epoch->flags = 0; |
| atomic_set(&epoch->epoch_size, 0); |
| atomic_set(&epoch->active, 0); |
| |
| spin_lock(&connection->epoch_lock); |
| if (atomic_read(&connection->current_epoch->epoch_size)) { |
| list_add(&epoch->list, &connection->current_epoch->list); |
| connection->current_epoch = epoch; |
| connection->epochs++; |
| } else { |
| /* The current_epoch got recycled while we allocated this one... */ |
| kfree(epoch); |
| } |
| spin_unlock(&connection->epoch_lock); |
| |
| return 0; |
| } |
| |
| /* used from receive_RSDataReply (recv_resync_read) |
| * and from receive_Data */ |
| static struct drbd_peer_request * |
| read_in_block(struct drbd_peer_device *peer_device, u64 id, sector_t sector, |
| struct packet_info *pi) __must_hold(local) |
| { |
| struct drbd_device *device = peer_device->device; |
| const sector_t capacity = drbd_get_capacity(device->this_bdev); |
| struct drbd_peer_request *peer_req; |
| struct page *page; |
| int digest_size, err; |
| unsigned int data_size = pi->size, ds; |
| void *dig_in = peer_device->connection->int_dig_in; |
| void *dig_vv = peer_device->connection->int_dig_vv; |
| unsigned long *data; |
| struct p_trim *trim = (pi->cmd == P_TRIM) ? pi->data : NULL; |
| |
| digest_size = 0; |
| if (!trim && peer_device->connection->peer_integrity_tfm) { |
| digest_size = crypto_hash_digestsize(peer_device->connection->peer_integrity_tfm); |
| /* |
| * FIXME: Receive the incoming digest into the receive buffer |
| * here, together with its struct p_data? |
| */ |
| err = drbd_recv_all_warn(peer_device->connection, dig_in, digest_size); |
| if (err) |
| return NULL; |
| data_size -= digest_size; |
| } |
| |
| if (trim) { |
| D_ASSERT(peer_device, data_size == 0); |
| data_size = be32_to_cpu(trim->size); |
| } |
| |
| if (!expect(IS_ALIGNED(data_size, 512))) |
| return NULL; |
| /* prepare for larger trim requests. */ |
| if (!trim && !expect(data_size <= DRBD_MAX_BIO_SIZE)) |
| return NULL; |
| |
| /* even though we trust out peer, |
| * we sometimes have to double check. */ |
| if (sector + (data_size>>9) > capacity) { |
| drbd_err(device, "request from peer beyond end of local disk: " |
| "capacity: %llus < sector: %llus + size: %u\n", |
| (unsigned long long)capacity, |
| (unsigned long long)sector, data_size); |
| return NULL; |
| } |
| |
| /* GFP_NOIO, because we must not cause arbitrary write-out: in a DRBD |
| * "criss-cross" setup, that might cause write-out on some other DRBD, |
| * which in turn might block on the other node at this very place. */ |
| peer_req = drbd_alloc_peer_req(peer_device, id, sector, data_size, trim == NULL, GFP_NOIO); |
| if (!peer_req) |
| return NULL; |
| |
| peer_req->flags |= EE_WRITE; |
| if (trim) |
| return peer_req; |
| |
| ds = data_size; |
| page = peer_req->pages; |
| page_chain_for_each(page) { |
| unsigned len = min_t(int, ds, PAGE_SIZE); |
| data = kmap(page); |
| err = drbd_recv_all_warn(peer_device->connection, data, len); |
| if (drbd_insert_fault(device, DRBD_FAULT_RECEIVE)) { |
| drbd_err(device, "Fault injection: Corrupting data on receive\n"); |
| data[0] = data[0] ^ (unsigned long)-1; |
| } |
| kunmap(page); |
| if (err) { |
| drbd_free_peer_req(device, peer_req); |
| return NULL; |
| } |
| ds -= len; |
| } |
| |
| if (digest_size) { |
| drbd_csum_ee(peer_device->connection->peer_integrity_tfm, peer_req, dig_vv); |
| if (memcmp(dig_in, dig_vv, digest_size)) { |
| drbd_err(device, "Digest integrity check FAILED: %llus +%u\n", |
| (unsigned long long)sector, data_size); |
| drbd_free_peer_req(device, peer_req); |
| return NULL; |
| } |
| } |
| device->recv_cnt += data_size >> 9; |
| return peer_req; |
| } |
| |
| /* drbd_drain_block() just takes a data block |
| * out of the socket input buffer, and discards it. |
| */ |
| static int drbd_drain_block(struct drbd_peer_device *peer_device, int data_size) |
| { |
| struct page *page; |
| int err = 0; |
| void *data; |
| |
| if (!data_size) |
| return 0; |
| |
| page = drbd_alloc_pages(peer_device, 1, 1); |
| |
| data = kmap(page); |
| while (data_size) { |
| unsigned int len = min_t(int, data_size, PAGE_SIZE); |
| |
| err = drbd_recv_all_warn(peer_device->connection, data, len); |
| if (err) |
| break; |
| data_size -= len; |
| } |
| kunmap(page); |
| drbd_free_pages(peer_device->device, page, 0); |
| return err; |
| } |
| |
| static int recv_dless_read(struct drbd_peer_device *peer_device, struct drbd_request *req, |
| sector_t sector, int data_size) |
| { |
| struct bio_vec bvec; |
| struct bvec_iter iter; |
| struct bio *bio; |
| int digest_size, err, expect; |
| void *dig_in = peer_device->connection->int_dig_in; |
| void *dig_vv = peer_device->connection->int_dig_vv; |
| |
| digest_size = 0; |
| if (peer_device->connection->peer_integrity_tfm) { |
| digest_size = crypto_hash_digestsize(peer_device->connection->peer_integrity_tfm); |
| err = drbd_recv_all_warn(peer_device->connection, dig_in, digest_size); |
| if (err) |
| return err; |
| data_size -= digest_size; |
| } |
| |
| /* optimistically update recv_cnt. if receiving fails below, |
| * we disconnect anyways, and counters will be reset. */ |
| peer_device->device->recv_cnt += data_size>>9; |
| |
| bio = req->master_bio; |
| D_ASSERT(peer_device->device, sector == bio->bi_iter.bi_sector); |
| |
| bio_for_each_segment(bvec, bio, iter) { |
| void *mapped = kmap(bvec.bv_page) + bvec.bv_offset; |
| expect = min_t(int, data_size, bvec.bv_len); |
| err = drbd_recv_all_warn(peer_device->connection, mapped, expect); |
| kunmap(bvec.bv_page); |
| if (err) |
| return err; |
| data_size -= expect; |
| } |
| |
| if (digest_size) { |
| drbd_csum_bio(peer_device->connection->peer_integrity_tfm, bio, dig_vv); |
| if (memcmp(dig_in, dig_vv, digest_size)) { |
| drbd_err(peer_device, "Digest integrity check FAILED. Broken NICs?\n"); |
| return -EINVAL; |
| } |
| } |
| |
| D_ASSERT(peer_device->device, data_size == 0); |
| return 0; |
| } |
| |
| /* |
| * e_end_resync_block() is called in asender context via |
| * drbd_finish_peer_reqs(). |
| */ |
| static int e_end_resync_block(struct drbd_work *w, int unused) |
| { |
| struct drbd_peer_request *peer_req = |
| container_of(w, struct drbd_peer_request, w); |
| struct drbd_peer_device *peer_device = peer_req->peer_device; |
| struct drbd_device *device = peer_device->device; |
| sector_t sector = peer_req->i.sector; |
| int err; |
| |
| D_ASSERT(device, drbd_interval_empty(&peer_req->i)); |
| |
| if (likely((peer_req->flags & EE_WAS_ERROR) == 0)) { |
| drbd_set_in_sync(device, sector, peer_req->i.size); |
| err = drbd_send_ack(peer_device, P_RS_WRITE_ACK, peer_req); |
| } else { |
| /* Record failure to sync */ |
| drbd_rs_failed_io(device, sector, peer_req->i.size); |
| |
| err = drbd_send_ack(peer_device, P_NEG_ACK, peer_req); |
| } |
| dec_unacked(device); |
| |
| return err; |
| } |
| |
| static int recv_resync_read(struct drbd_peer_device *peer_device, sector_t sector, |
| struct packet_info *pi) __releases(local) |
| { |
| struct drbd_device *device = peer_device->device; |
| struct drbd_peer_request *peer_req; |
| |
| peer_req = read_in_block(peer_device, ID_SYNCER, sector, pi); |
| if (!peer_req) |
| goto fail; |
| |
| dec_rs_pending(device); |
| |
| inc_unacked(device); |
| /* corresponding dec_unacked() in e_end_resync_block() |
| * respective _drbd_clear_done_ee */ |
| |
| peer_req->w.cb = e_end_resync_block; |
| peer_req->submit_jif = jiffies; |
| |
| spin_lock_irq(&device->resource->req_lock); |
| list_add_tail(&peer_req->w.list, &device->sync_ee); |
| spin_unlock_irq(&device->resource->req_lock); |
| |
| atomic_add(pi->size >> 9, &device->rs_sect_ev); |
| if (drbd_submit_peer_request(device, peer_req, WRITE, DRBD_FAULT_RS_WR) == 0) |
| return 0; |
| |
| /* don't care for the reason here */ |
| drbd_err(device, "submit failed, triggering re-connect\n"); |
| spin_lock_irq(&device->resource->req_lock); |
| list_del(&peer_req->w.list); |
| spin_unlock_irq(&device->resource->req_lock); |
| |
| drbd_free_peer_req(device, peer_req); |
| fail: |
| put_ldev(device); |
| return -EIO; |
| } |
| |
| static struct drbd_request * |
| find_request(struct drbd_device *device, struct rb_root *root, u64 id, |
| sector_t sector, bool missing_ok, const char *func) |
| { |
| struct drbd_request *req; |
| |
| /* Request object according to our peer */ |
| req = (struct drbd_request *)(unsigned long)id; |
| if (drbd_contains_interval(root, sector, &req->i) && req->i.local) |
| return req; |
| if (!missing_ok) { |
| drbd_err(device, "%s: failed to find request 0x%lx, sector %llus\n", func, |
| (unsigned long)id, (unsigned long long)sector); |
| } |
| return NULL; |
| } |
| |
| static int receive_DataReply(struct drbd_connection *connection, struct packet_info *pi) |
| { |
| struct drbd_peer_device *peer_device; |
| struct drbd_device *device; |
| struct drbd_request *req; |
| sector_t sector; |
| int err; |
| struct p_data *p = pi->data; |
| |
| peer_device = conn_peer_device(connection, pi->vnr); |
| if (!peer_device) |
| return -EIO; |
| device = peer_device->device; |
| |
| sector = be64_to_cpu(p->sector); |
| |
| spin_lock_irq(&device->resource->req_lock); |
| req = find_request(device, &device->read_requests, p->block_id, sector, false, __func__); |
| spin_unlock_irq(&device->resource->req_lock); |
| if (unlikely(!req)) |
| return -EIO; |
| |
| /* hlist_del(&req->collision) is done in _req_may_be_done, to avoid |
| * special casing it there for the various failure cases. |
| * still no race with drbd_fail_pending_reads */ |
| err = recv_dless_read(peer_device, req, sector, pi->size); |
| if (!err) |
| req_mod(req, DATA_RECEIVED); |
| /* else: nothing. handled from drbd_disconnect... |
| * I don't think we may complete this just yet |
| * in case we are "on-disconnect: freeze" */ |
| |
| return err; |
| } |
| |
| static int receive_RSDataReply(struct drbd_connection *connection, struct packet_info *pi) |
| { |
| struct drbd_peer_device *peer_device; |
| struct drbd_device *device; |
| sector_t sector; |
| int err; |
| struct p_data *p = pi->data; |
| |
| peer_device = conn_peer_device(connection, pi->vnr); |
| if (!peer_device) |
| return -EIO; |
| device = peer_device->device; |
| |
| sector = be64_to_cpu(p->sector); |
| D_ASSERT(device, p->block_id == ID_SYNCER); |
| |
| if (get_ldev(device)) { |
| /* data is submitted to disk within recv_resync_read. |
| * corresponding put_ldev done below on error, |
| * or in drbd_peer_request_endio. */ |
| err = recv_resync_read(peer_device, sector, pi); |
| } else { |
| if (__ratelimit(&drbd_ratelimit_state)) |
| drbd_err(device, "Can not write resync data to local disk.\n"); |
| |
| err = drbd_drain_block(peer_device, pi->size); |
| |
| drbd_send_ack_dp(peer_device, P_NEG_ACK, p, pi->size); |
| } |
| |
| atomic_add(pi->size >> 9, &device->rs_sect_in); |
| |
| return err; |
| } |
| |
| static void restart_conflicting_writes(struct drbd_device *device, |
| sector_t sector, int size) |
| { |
| struct drbd_interval *i; |
| struct drbd_request *req; |
| |
| drbd_for_each_overlap(i, &device->write_requests, sector, size) { |
| if (!i->local) |
| continue; |
| req = container_of(i, struct drbd_request, i); |
| if (req->rq_state & RQ_LOCAL_PENDING || |
| !(req->rq_state & RQ_POSTPONED)) |
| continue; |
| /* as it is RQ_POSTPONED, this will cause it to |
| * be queued on the retry workqueue. */ |
| __req_mod(req, CONFLICT_RESOLVED, NULL); |
| } |
| } |
| |
| /* |
| * e_end_block() is called in asender context via drbd_finish_peer_reqs(). |
| */ |
| static int e_end_block(struct drbd_work *w, int cancel) |
| { |
| struct drbd_peer_request *peer_req = |
| container_of(w, struct drbd_peer_request, w); |
| struct drbd_peer_device *peer_device = peer_req->peer_device; |
| struct drbd_device *device = peer_device->device; |
| sector_t sector = peer_req->i.sector; |
| int err = 0, pcmd; |
| |
| if (peer_req->flags & EE_SEND_WRITE_ACK) { |
| if (likely((peer_req->flags & EE_WAS_ERROR) == 0)) { |
| pcmd = (device->state.conn >= C_SYNC_SOURCE && |
| device->state.conn <= C_PAUSED_SYNC_T && |
| peer_req->flags & EE_MAY_SET_IN_SYNC) ? |
| P_RS_WRITE_ACK : P_WRITE_ACK; |
| err = drbd_send_ack(peer_device, pcmd, peer_req); |
| if (pcmd == P_RS_WRITE_ACK) |
| drbd_set_in_sync(device, sector, peer_req->i.size); |
| } else { |
| err = drbd_send_ack(peer_device, P_NEG_ACK, peer_req); |
| /* we expect it to be marked out of sync anyways... |
| * maybe assert this? */ |
| } |
| dec_unacked(device); |
| } |
| |
| /* we delete from the conflict detection hash _after_ we sent out the |
| * P_WRITE_ACK / P_NEG_ACK, to get the sequence number right. */ |
| if (peer_req->flags & EE_IN_INTERVAL_TREE) { |
| spin_lock_irq(&device->resource->req_lock); |
| D_ASSERT(device, !drbd_interval_empty(&peer_req->i)); |
| drbd_remove_epoch_entry_interval(device, peer_req); |
| if (peer_req->flags & EE_RESTART_REQUESTS) |
| restart_conflicting_writes(device, sector, peer_req->i.size); |
| spin_unlock_irq(&device->resource->req_lock); |
| } else |
| D_ASSERT(device, drbd_interval_empty(&peer_req->i)); |
| |
| drbd_may_finish_epoch(first_peer_device(device)->connection, peer_req->epoch, EV_PUT + (cancel ? EV_CLEANUP : 0)); |
| |
| return err; |
| } |
| |
| static int e_send_ack(struct drbd_work *w, enum drbd_packet ack) |
| { |
| struct drbd_peer_request *peer_req = |
| container_of(w, struct drbd_peer_request, w); |
| struct drbd_peer_device *peer_device = peer_req->peer_device; |
| int err; |
| |
| err = drbd_send_ack(peer_device, ack, peer_req); |
| dec_unacked(peer_device->device); |
| |
| return err; |
| } |
| |
| static int e_send_superseded(struct drbd_work *w, int unused) |
| { |
| return e_send_ack(w, P_SUPERSEDED); |
| } |
| |
| static int e_send_retry_write(struct drbd_work *w, int unused) |
| { |
| struct drbd_peer_request *peer_req = |
| container_of(w, struct drbd_peer_request, w); |
| struct drbd_connection *connection = peer_req->peer_device->connection; |
| |
| return e_send_ack(w, connection->agreed_pro_version >= 100 ? |
| P_RETRY_WRITE : P_SUPERSEDED); |
| } |
| |
| static bool seq_greater(u32 a, u32 b) |
| { |
| /* |
| * We assume 32-bit wrap-around here. |
| * For 24-bit wrap-around, we would have to shift: |
| * a <<= 8; b <<= 8; |
| */ |
| return (s32)a - (s32)b > 0; |
| } |
| |
| static u32 seq_max(u32 a, u32 b) |
| { |
| return seq_greater(a, b) ? a : b; |
| } |
| |
| static void update_peer_seq(struct drbd_peer_device *peer_device, unsigned int peer_seq) |
| { |
| struct drbd_device *device = peer_device->device; |
| unsigned int newest_peer_seq; |
| |
| if (test_bit(RESOLVE_CONFLICTS, &peer_device->connection->flags)) { |
| spin_lock(&device->peer_seq_lock); |
| newest_peer_seq = seq_max(device->peer_seq, peer_seq); |
| device->peer_seq = newest_peer_seq; |
| spin_unlock(&device->peer_seq_lock); |
| /* wake up only if we actually changed device->peer_seq */ |
| if (peer_seq == newest_peer_seq) |
| wake_up(&device->seq_wait); |
| } |
| } |
| |
| static inline int overlaps(sector_t s1, int l1, sector_t s2, int l2) |
| { |
| return !((s1 + (l1>>9) <= s2) || (s1 >= s2 + (l2>>9))); |
| } |
| |
| /* maybe change sync_ee into interval trees as well? */ |
| static bool overlapping_resync_write(struct drbd_device *device, struct drbd_peer_request *peer_req) |
| { |
| struct drbd_peer_request *rs_req; |
| bool rv = 0; |
| |
| spin_lock_irq(&device->resource->req_lock); |
| list_for_each_entry(rs_req, &device->sync_ee, w.list) { |
| if (overlaps(peer_req->i.sector, peer_req->i.size, |
| rs_req->i.sector, rs_req->i.size)) { |
| rv = 1; |
| break; |
| } |
| } |
| spin_unlock_irq(&device->resource->req_lock); |
| |
| return rv; |
| } |
| |
| /* Called from receive_Data. |
| * Synchronize packets on sock with packets on msock. |
| * |
| * This is here so even when a P_DATA packet traveling via sock overtook an Ack |
| * packet traveling on msock, they are still processed in the order they have |
| * been sent. |
| * |
| * Note: we don't care for Ack packets overtaking P_DATA packets. |
| * |
| * In case packet_seq is larger than device->peer_seq number, there are |
| * outstanding packets on the msock. We wait for them to arrive. |
| * In case we are the logically next packet, we update device->peer_seq |
| * ourselves. Correctly handles 32bit wrap around. |
| * |
| * Assume we have a 10 GBit connection, that is about 1<<30 byte per second, |
| * about 1<<21 sectors per second. So "worst" case, we have 1<<3 == 8 seconds |
| * for the 24bit wrap (historical atomic_t guarantee on some archs), and we have |
| * 1<<9 == 512 seconds aka ages for the 32bit wrap around... |
| * |
| * returns 0 if we may process the packet, |
| * -ERESTARTSYS if we were interrupted (by disconnect signal). */ |
| static int wait_for_and_update_peer_seq(struct drbd_peer_device *peer_device, const u32 peer_seq) |
| { |
| struct drbd_device *device = peer_device->device; |
| DEFINE_WAIT(wait); |
| long timeout; |
| int ret = 0, tp; |
| |
| if (!test_bit(RESOLVE_CONFLICTS, &peer_device->connection->flags)) |
| return 0; |
| |
| spin_lock(&device->peer_seq_lock); |
| for (;;) { |
| if (!seq_greater(peer_seq - 1, device->peer_seq)) { |
| device->peer_seq = seq_max(device->peer_seq, peer_seq); |
| break; |
| } |
| |
| if (signal_pending(current)) { |
| ret = -ERESTARTSYS; |
| break; |
| } |
| |
| rcu_read_lock(); |
| tp = rcu_dereference(first_peer_device(device)->connection->net_conf)->two_primaries; |
| rcu_read_unlock(); |
| |
| if (!tp) |
| break; |
| |
| /* Only need to wait if two_primaries is enabled */ |
| prepare_to_wait(&device->seq_wait, &wait, TASK_INTERRUPTIBLE); |
| spin_unlock(&device->peer_seq_lock); |
| rcu_read_lock(); |
| timeout = rcu_dereference(peer_device->connection->net_conf)->ping_timeo*HZ/10; |
| rcu_read_unlock(); |
| timeout = schedule_timeout(timeout); |
| spin_lock(&device->peer_seq_lock); |
| if (!timeout) { |
| ret = -ETIMEDOUT; |
| drbd_err(device, "Timed out waiting for missing ack packets; disconnecting\n"); |
| break; |
| } |
| } |
| spin_unlock(&device->peer_seq_lock); |
| finish_wait(&device->seq_wait, &wait); |
| return ret; |
| } |
| |
| /* see also bio_flags_to_wire() |
| * DRBD_REQ_*, because we need to semantically map the flags to data packet |
| * flags and back. We may replicate to other kernel versions. */ |
| static unsigned long wire_flags_to_bio(u32 dpf) |
| { |
| return (dpf & DP_RW_SYNC ? REQ_SYNC : 0) | |
| (dpf & DP_FUA ? REQ_FUA : 0) | |
| (dpf & DP_FLUSH ? REQ_FLUSH : 0) | |
| (dpf & DP_DISCARD ? REQ_DISCARD : 0); |
| } |
| |
| static void fail_postponed_requests(struct drbd_device *device, sector_t sector, |
| unsigned int size) |
| { |
| struct drbd_interval *i; |
| |
| repeat: |
| drbd_for_each_overlap(i, &device->write_requests, sector, size) { |
| struct drbd_request *req; |
| struct bio_and_error m; |
| |
| if (!i->local) |
| continue; |
| req = container_of(i, struct drbd_request, i); |
| if (!(req->rq_state & RQ_POSTPONED)) |
| continue; |
| req->rq_state &= ~RQ_POSTPONED; |
| __req_mod(req, NEG_ACKED, &m); |
| spin_unlock_irq(&device->resource->req_lock); |
| if (m.bio) |
| complete_master_bio(device, &m); |
| spin_lock_irq(&device->resource->req_lock); |
| goto repeat; |
| } |
| } |
| |
| static int handle_write_conflicts(struct drbd_device *device, |
| struct drbd_peer_request *peer_req) |
| { |
| struct drbd_connection *connection = peer_req->peer_device->connection; |
| bool resolve_conflicts = test_bit(RESOLVE_CONFLICTS, &connection->flags); |
| sector_t sector = peer_req->i.sector; |
| const unsigned int size = peer_req->i.size; |
| struct drbd_interval *i; |
| bool equal; |
| int err; |
| |
| /* |
| * Inserting the peer request into the write_requests tree will prevent |
| * new conflicting local requests from being added. |
| */ |
| drbd_insert_interval(&device->write_requests, &peer_req->i); |
| |
| repeat: |
| drbd_for_each_overlap(i, &device->write_requests, sector, size) { |
| if (i == &peer_req->i) |
| continue; |
| if (i->completed) |
| continue; |
| |
| if (!i->local) { |
| /* |
| * Our peer has sent a conflicting remote request; this |
| * should not happen in a two-node setup. Wait for the |
| * earlier peer request to complete. |
| */ |
| err = drbd_wait_misc(device, i); |
| if (err) |
| goto out; |
| goto repeat; |
| } |
| |
| equal = i->sector == sector && i->size == size; |
| if (resolve_conflicts) { |
| /* |
| * If the peer request is fully contained within the |
| * overlapping request, it can be considered overwritten |
| * and thus superseded; otherwise, it will be retried |
| * once all overlapping requests have completed. |
| */ |
| bool superseded = i->sector <= sector && i->sector + |
| (i->size >> 9) >= sector + (size >> 9); |
| |
| if (!equal) |
| drbd_alert(device, "Concurrent writes detected: " |
| "local=%llus +%u, remote=%llus +%u, " |
| "assuming %s came first\n", |
| (unsigned long long)i->sector, i->size, |
| (unsigned long long)sector, size, |
| superseded ? "local" : "remote"); |
| |
| peer_req->w.cb = superseded ? e_send_superseded : |
| e_send_retry_write; |
| list_add_tail(&peer_req->w.list, &device->done_ee); |
| wake_asender(connection); |
| |
| err = -ENOENT; |
| goto out; |
| } else { |
| struct drbd_request *req = |
| container_of(i, struct drbd_request, i); |
| |
| if (!equal) |
| drbd_alert(device, "Concurrent writes detected: " |
| "local=%llus +%u, remote=%llus +%u\n", |
| (unsigned long long)i->sector, i->size, |
| (unsigned long long)sector, size); |
| |
| if (req->rq_state & RQ_LOCAL_PENDING || |
| !(req->rq_state & RQ_POSTPONED)) { |
| /* |
| * Wait for the node with the discard flag to |
| * decide if this request has been superseded |
| * or needs to be retried. |
| * Requests that have been superseded will |
| * disappear from the write_requests tree. |
| * |
| * In addition, wait for the conflicting |
| * request to finish locally before submitting |
| * the conflicting peer request. |
| */ |
| err = drbd_wait_misc(device, &req->i); |
| if (err) { |
| _conn_request_state(connection, NS(conn, C_TIMEOUT), CS_HARD); |
| fail_postponed_requests(device, sector, size); |
| goto out; |
| } |
| goto repeat; |
| } |
| /* |
| * Remember to restart the conflicting requests after |
| * the new peer request has completed. |
| */ |
| peer_req->flags |= EE_RESTART_REQUESTS; |
| } |
| } |
| err = 0; |
| |
| out: |
| if (err) |
| drbd_remove_epoch_entry_interval(device, peer_req); |
| return err; |
| } |
| |
| /* mirrored write */ |
| static int receive_Data(struct drbd_connection *connection, struct packet_info *pi) |
| { |
| struct drbd_peer_device *peer_device; |
| struct drbd_device *device; |
| struct net_conf *nc; |
| sector_t sector; |
| struct drbd_peer_request *peer_req; |
| struct p_data *p = pi->data; |
| u32 peer_seq = be32_to_cpu(p->seq_num); |
| int rw = WRITE; |
| u32 dp_flags; |
| int err, tp; |
| |
| peer_device = conn_peer_device(connection, pi->vnr); |
| if (!peer_device) |
| return -EIO; |
| device = peer_device->device; |
| |
| if (!get_ldev(device)) { |
| int err2; |
| |
| err = wait_for_and_update_peer_seq(peer_device, peer_seq); |
| drbd_send_ack_dp(peer_device, P_NEG_ACK, p, pi->size); |
| atomic_inc(&connection->current_epoch->epoch_size); |
| err2 = drbd_drain_block(peer_device, pi->size); |
| if (!err) |
| err = err2; |
| return err; |
| } |
| |
| /* |
| * Corresponding put_ldev done either below (on various errors), or in |
| * drbd_peer_request_endio, if we successfully submit the data at the |
| * end of this function. |
| */ |
| |
| sector = be64_to_cpu(p->sector); |
| peer_req = read_in_block(peer_device, p->block_id, sector, pi); |
| if (!peer_req) { |
| put_ldev(device); |
| return -EIO; |
| } |
| |
| peer_req->w.cb = e_end_block; |
| peer_req->submit_jif = jiffies; |
| peer_req->flags |= EE_APPLICATION; |
| |
| dp_flags = be32_to_cpu(p->dp_flags); |
| rw |= wire_flags_to_bio(dp_flags); |
| if (pi->cmd == P_TRIM) { |
| struct request_queue *q = bdev_get_queue(device->ldev->backing_bdev); |
| peer_req->flags |= EE_IS_TRIM; |
| if (!blk_queue_discard(q)) |
| peer_req->flags |= EE_IS_TRIM_USE_ZEROOUT; |
| D_ASSERT(peer_device, peer_req->i.size > 0); |
| D_ASSERT(peer_device, rw & REQ_DISCARD); |
| D_ASSERT(peer_device, peer_req->pages == NULL); |
| } else if (peer_req->pages == NULL) { |
| D_ASSERT(device, peer_req->i.size == 0); |
| D_ASSERT(device, dp_flags & DP_FLUSH); |
| } |
| |
| if (dp_flags & DP_MAY_SET_IN_SYNC) |
| peer_req->flags |= EE_MAY_SET_IN_SYNC; |
| |
| spin_lock(&connection->epoch_lock); |
| peer_req->epoch = connection->current_epoch; |
| atomic_inc(&peer_req->epoch->epoch_size); |
| atomic_inc(&peer_req->epoch->active); |
| spin_unlock(&connection->epoch_lock); |
| |
| rcu_read_lock(); |
| nc = rcu_dereference(peer_device->connection->net_conf); |
| tp = nc->two_primaries; |
| if (peer_device->connection->agreed_pro_version < 100) { |
| switch (nc->wire_protocol) { |
| case DRBD_PROT_C: |
| dp_flags |= DP_SEND_WRITE_ACK; |
| break; |
| case DRBD_PROT_B: |
| dp_flags |= DP_SEND_RECEIVE_ACK; |
| break; |
| } |
| } |
| rcu_read_unlock(); |
| |
| if (dp_flags & DP_SEND_WRITE_ACK) { |
| peer_req->flags |= EE_SEND_WRITE_ACK; |
| inc_unacked(device); |
| /* corresponding dec_unacked() in e_end_block() |
| * respective _drbd_clear_done_ee */ |
| } |
| |
| if (dp_flags & DP_SEND_RECEIVE_ACK) { |
| /* I really don't like it that the receiver thread |
| * sends on the msock, but anyways */ |
| drbd_send_ack(first_peer_device(device), P_RECV_ACK, peer_req); |
| } |
| |
| if (tp) { |
| /* two primaries implies protocol C */ |
| D_ASSERT(device, dp_flags & DP_SEND_WRITE_ACK); |
| peer_req->flags |= EE_IN_INTERVAL_TREE; |
| err = wait_for_and_update_peer_seq(peer_device, peer_seq); |
| if (err) |
| goto out_interrupted; |
| spin_lock_irq(&device->resource->req_lock); |
| err = handle_write_conflicts(device, peer_req); |
| if (err) { |
| spin_unlock_irq(&device->resource->req_lock); |
| if (err == -ENOENT) { |
| put_ldev(device); |
| return 0; |
| } |
| goto out_interrupted; |
| } |
| } else { |
| update_peer_seq(peer_device, peer_seq); |
| spin_lock_irq(&device->resource->req_lock); |
| } |
| /* if we use the zeroout fallback code, we process synchronously |
| * and we wait for all pending requests, respectively wait for |
| * active_ee to become empty in drbd_submit_peer_request(); |
| * better not add ourselves here. */ |
| if ((peer_req->flags & EE_IS_TRIM_USE_ZEROOUT) == 0) |
| list_add_tail(&peer_req->w.list, &device->active_ee); |
| spin_unlock_irq(&device->resource->req_lock); |
| |
| if (device->state.conn == C_SYNC_TARGET) |
| wait_event(device->ee_wait, !overlapping_resync_write(device, peer_req)); |
| |
| if (device->state.pdsk < D_INCONSISTENT) { |
| /* In case we have the only disk of the cluster, */ |
| drbd_set_out_of_sync(device, peer_req->i.sector, peer_req->i.size); |
| peer_req->flags &= ~EE_MAY_SET_IN_SYNC; |
| drbd_al_begin_io(device, &peer_req->i); |
| peer_req->flags |= EE_CALL_AL_COMPLETE_IO; |
| } |
| |
| err = drbd_submit_peer_request(device, peer_req, rw, DRBD_FAULT_DT_WR); |
| if (!err) |
| return 0; |
| |
| /* don't care for the reason here */ |
| drbd_err(device, "submit failed, triggering re-connect\n"); |
| spin_lock_irq(&device->resource->req_lock); |
| list_del(&peer_req->w.list); |
| drbd_remove_epoch_entry_interval(device, peer_req); |
| spin_unlock_irq(&device->resource->req_lock); |
| if (peer_req->flags & EE_CALL_AL_COMPLETE_IO) { |
| peer_req->flags &= ~EE_CALL_AL_COMPLETE_IO; |
| drbd_al_complete_io(device, &peer_req->i); |
| } |
| |
| out_interrupted: |
| drbd_may_finish_epoch(connection, peer_req->epoch, EV_PUT + EV_CLEANUP); |
| put_ldev(device); |
| drbd_free_peer_req(device, peer_req); |
| return err; |
| } |
| |
| /* We may throttle resync, if the lower device seems to be busy, |
| * and current sync rate is above c_min_rate. |
| * |
| * To decide whether or not the lower device is busy, we use a scheme similar |
| * to MD RAID is_mddev_idle(): if the partition stats reveal "significant" |
| * (more than 64 sectors) of activity we cannot account for with our own resync |
| * activity, it obviously is "busy". |
| * |
| * The current sync rate used here uses only the most recent two step marks, |
| * to have a short time average so we can react faster. |
| */ |
| bool drbd_rs_should_slow_down(struct drbd_device *device, sector_t sector, |
| bool throttle_if_app_is_waiting) |
| { |
| struct lc_element *tmp; |
| bool throttle = drbd_rs_c_min_rate_throttle(device); |
| |
| if (!throttle || throttle_if_app_is_waiting) |
| return throttle; |
| |
| spin_lock_irq(&device->al_lock); |
| tmp = lc_find(device->resync, BM_SECT_TO_EXT(sector)); |
| if (tmp) { |
| struct bm_extent *bm_ext = lc_entry(tmp, struct bm_extent, lce); |
| if (test_bit(BME_PRIORITY, &bm_ext->flags)) |
| throttle = false; |
| /* Do not slow down if app IO is already waiting for this extent, |
| * and our progress is necessary for application IO to complete. */ |
| } |
| spin_unlock_irq(&device->al_lock); |
| |
| return throttle; |
| } |
| |
| bool drbd_rs_c_min_rate_throttle(struct drbd_device *device) |
| { |
| struct gendisk *disk = device->ldev->backing_bdev->bd_contains->bd_disk; |
| unsigned long db, dt, dbdt; |
| unsigned int c_min_rate; |
| int curr_events; |
| |
| rcu_read_lock(); |
| c_min_rate = rcu_dereference(device->ldev->disk_conf)->c_min_rate; |
| rcu_read_unlock(); |
| |
| /* feature disabled? */ |
| if (c_min_rate == 0) |
| return false; |
| |
| curr_events = (int)part_stat_read(&disk->part0, sectors[0]) + |
| (int)part_stat_read(&disk->part0, sectors[1]) - |
| atomic_read(&device->rs_sect_ev); |
| |
| if (atomic_read(&device->ap_actlog_cnt) |
| || curr_events - device->rs_last_events > 64) { |
| unsigned long rs_left; |
| int i; |
| |
| device->rs_last_events = curr_events; |
| |
| /* sync speed average over the last 2*DRBD_SYNC_MARK_STEP, |
| * approx. */ |
| i = (device->rs_last_mark + DRBD_SYNC_MARKS-1) % DRBD_SYNC_MARKS; |
| |
| if (device->state.conn == C_VERIFY_S || device->state.conn == C_VERIFY_T) |
| rs_left = device->ov_left; |
| else |
| rs_left = drbd_bm_total_weight(device) - device->rs_failed; |
| |
| dt = ((long)jiffies - (long)device->rs_mark_time[i]) / HZ; |
| if (!dt) |
| dt++; |
| db = device->rs_mark_left[i] - rs_left; |
| dbdt = Bit2KB(db/dt); |
| |
| if (dbdt > c_min_rate) |
| return true; |
| } |
| return false; |
| } |
| |
| static int receive_DataRequest(struct drbd_connection *connection, struct packet_info *pi) |
| { |
| struct drbd_peer_device *peer_device; |
| struct drbd_device *device; |
| sector_t sector; |
| sector_t capacity; |
| struct drbd_peer_request *peer_req; |
| struct digest_info *di = NULL; |
| int size, verb; |
| unsigned int fault_type; |
| struct p_block_req *p = pi->data; |
| |
| peer_device = conn_peer_device(connection, pi->vnr); |
| if (!peer_device) |
| return -EIO; |
| device = peer_device->device; |
| capacity = drbd_get_capacity(device->this_bdev); |
| |
| sector = be64_to_cpu(p->sector); |
| size = be32_to_cpu(p->blksize); |
| |
| if (size <= 0 || !IS_ALIGNED(size, 512) || size > DRBD_MAX_BIO_SIZE) { |
| drbd_err(device, "%s:%d: sector: %llus, size: %u\n", __FILE__, __LINE__, |
| (unsigned long long)sector, size); |
| return -EINVAL; |
| } |
| if (sector + (size>>9) > capacity) { |
| drbd_err(device, "%s:%d: sector: %llus, size: %u\n", __FILE__, __LINE__, |
| (unsigned long long)sector, size); |
| return -EINVAL; |
| } |
| |
| if (!get_ldev_if_state(device, D_UP_TO_DATE)) { |
| verb = 1; |
| switch (pi->cmd) { |
| case P_DATA_REQUEST: |
| drbd_send_ack_rp(peer_device, P_NEG_DREPLY, p); |
| break; |
| case P_RS_DATA_REQUEST: |
| case P_CSUM_RS_REQUEST: |
| case P_OV_REQUEST: |
| drbd_send_ack_rp(peer_device, P_NEG_RS_DREPLY , p); |
| break; |
| case P_OV_REPLY: |
| verb = 0; |
| dec_rs_pending(device); |
| drbd_send_ack_ex(peer_device, P_OV_RESULT, sector, size, ID_IN_SYNC); |
| break; |
| default: |
| BUG(); |
| } |
| if (verb && __ratelimit(&drbd_ratelimit_state)) |
| drbd_err(device, "Can not satisfy peer's read request, " |
| "no local data.\n"); |
| |
| /* drain possibly payload */ |
| return drbd_drain_block(peer_device, pi->size); |
| } |
| |
| /* GFP_NOIO, because we must not cause arbitrary write-out: in a DRBD |
| * "criss-cross" setup, that might cause write-out on some other DRBD, |
| * which in turn might block on the other node at this very place. */ |
| peer_req = drbd_alloc_peer_req(peer_device, p->block_id, sector, size, |
| true /* has real payload */, GFP_NOIO); |
| if (!peer_req) { |
| put_ldev(device); |
| return -ENOMEM; |
| } |
| |
| switch (pi->cmd) { |
| case P_DATA_REQUEST: |
| peer_req->w.cb = w_e_end_data_req; |
| fault_type = DRBD_FAULT_DT_RD; |
| /* application IO, don't drbd_rs_begin_io */ |
| peer_req->flags |= EE_APPLICATION; |
| goto submit; |
| |
| case P_RS_DATA_REQUEST: |
| peer_req->w.cb = w_e_end_rsdata_req; |
| fault_type = DRBD_FAULT_RS_RD; |
| /* used in the sector offset progress display */ |
| device->bm_resync_fo = BM_SECT_TO_BIT(sector); |
| break; |
| |
| case P_OV_REPLY: |
| case P_CSUM_RS_REQUEST: |
| fault_type = DRBD_FAULT_RS_RD; |
| di = kmalloc(sizeof(*di) + pi->size, GFP_NOIO); |
| if (!di) |
| goto out_free_e; |
| |
| di->digest_size = pi->size; |
| di->digest = (((char *)di)+sizeof(struct digest_info)); |
| |
| peer_req->digest = di; |
| peer_req->flags |= EE_HAS_DIGEST; |
| |
| if (drbd_recv_all(peer_device->connection, di->digest, pi->size)) |
| goto out_free_e; |
| |
| if (pi->cmd == P_CSUM_RS_REQUEST) { |
| D_ASSERT(device, peer_device->connection->agreed_pro_version >= 89); |
| peer_req->w.cb = w_e_end_csum_rs_req; |
| /* used in the sector offset progress display */ |
| device->bm_resync_fo = BM_SECT_TO_BIT(sector); |
| /* remember to report stats in drbd_resync_finished */ |
| device->use_csums = true; |
| } else if (pi->cmd == P_OV_REPLY) { |
| /* track progress, we may need to throttle */ |
| atomic_add(size >> 9, &device->rs_sect_in); |
| peer_req->w.cb = w_e_end_ov_reply; |
| dec_rs_pending(device); |
| /* drbd_rs_begin_io done when we sent this request, |
| * but accounting still needs to be done. */ |
| goto submit_for_resync; |
| } |
| break; |
| |
| case P_OV_REQUEST: |
| if (device->ov_start_sector == ~(sector_t)0 && |
| peer_device->connection->agreed_pro_version >= 90) { |
| unsigned long now = jiffies; |
| int i; |
| device->ov_start_sector = sector; |
| device->ov_position = sector; |
| device->ov_left = drbd_bm_bits(device) - BM_SECT_TO_BIT(sector); |
| device->rs_total = device->ov_left; |
| for (i = 0; i < DRBD_SYNC_MARKS; i++) { |
| device->rs_mark_left[i] = device->ov_left; |
| device->rs_mark_time[i] = now; |
| } |
| drbd_info(device, "Online Verify start sector: %llu\n", |
| (unsigned long long)sector); |
| } |
| peer_req->w.cb = w_e_end_ov_req; |
| fault_type = DRBD_FAULT_RS_RD; |
| break; |
| |
| default: |
| BUG(); |
| } |
| |
| /* Throttle, drbd_rs_begin_io and submit should become asynchronous |
| * wrt the receiver, but it is not as straightforward as it may seem. |
| * Various places in the resync start and stop logic assume resync |
| * requests are processed in order, requeuing this on the worker thread |
| * introduces a bunch of new code for synchronization between threads. |
| * |
| * Unlimited throttling before drbd_rs_begin_io may stall the resync |
| * "forever", throttling after drbd_rs_begin_io will lock that extent |
| * for application writes for the same time. For now, just throttle |
| * here, where the rest of the code expects the receiver to sleep for |
| * a while, anyways. |
| */ |
| |
| /* Throttle before drbd_rs_begin_io, as that locks out application IO; |
| * this defers syncer requests for some time, before letting at least |
| * on request through. The resync controller on the receiving side |
| * will adapt to the incoming rate accordingly. |
| * |
| * We cannot throttle here if remote is Primary/SyncTarget: |
| * we would also throttle its application reads. |
| * In that case, throttling is done on the SyncTarget only. |
| */ |
| |
| /* Even though this may be a resync request, we do add to "read_ee"; |
| * "sync_ee" is only used for resync WRITEs. |
| * Add to list early, so debugfs can find this request |
| * even if we have to sleep below. */ |
| spin_lock_irq(&device->resource->req_lock); |
| list_add_tail(&peer_req->w.list, &device->read_ee); |
| spin_unlock_irq(&device->resource->req_lock); |
| |
| update_receiver_timing_details(connection, drbd_rs_should_slow_down); |
| if (device->state.peer != R_PRIMARY |
| && drbd_rs_should_slow_down(device, sector, false)) |
| schedule_timeout_uninterruptible(HZ/10); |
| update_receiver_timing_details(connection, drbd_rs_begin_io); |
| if (drbd_rs_begin_io(device, sector)) |
| goto out_free_e; |
| |
| submit_for_resync: |
| atomic_add(size >> 9, &device->rs_sect_ev); |
| |
| submit: |
| update_receiver_timing_details(connection, drbd_submit_peer_request); |
| inc_unacked(device); |
| if (drbd_submit_peer_request(device, peer_req, READ, fault_type) == 0) |
| return 0; |
| |
| /* don't care for the reason here */ |
| drbd_err(device, "submit failed, triggering re-connect\n"); |
| |
| out_free_e: |
| spin_lock_irq(&device->resource->req_lock); |
| list_del(&peer_req->w.list); |
| spin_unlock_irq(&device->resource->req_lock); |
| /* no drbd_rs_complete_io(), we are dropping the connection anyways */ |
| |
| put_ldev(device); |
| drbd_free_peer_req(device, peer_req); |
| return -EIO; |
| } |
| |
| /** |
| * drbd_asb_recover_0p - Recover after split-brain with no remaining primaries |
| */ |
| static int drbd_asb_recover_0p(struct drbd_peer_device *peer_device) __must_hold(local) |
| { |
| struct drbd_device *device = peer_device->device; |
| int self, peer, rv = -100; |
| unsigned long ch_self, ch_peer; |
| enum drbd_after_sb_p after_sb_0p; |
| |
| self = device->ldev->md.uuid[UI_BITMAP] & 1; |
| peer = device->p_uuid[UI_BITMAP] & 1; |
| |
| ch_peer = device->p_uuid[UI_SIZE]; |
| ch_self = device->comm_bm_set; |
| |
| rcu_read_lock(); |
| after_sb_0p = rcu_dereference(peer_device->connection->net_conf)->after_sb_0p; |
| rcu_read_unlock(); |
| switch (after_sb_0p) { |
| case ASB_CONSENSUS: |
| case ASB_DISCARD_SECONDARY: |
| case ASB_CALL_HELPER: |
| case ASB_VIOLENTLY: |
| drbd_err(device, "Configuration error.\n"); |
| break; |
| case ASB_DISCONNECT: |
| break; |
| case ASB_DISCARD_YOUNGER_PRI: |
| if (self == 0 && peer == 1) { |
| rv = -1; |
| break; |
| } |
| if (self == 1 && peer == 0) { |
| rv = 1; |
| break; |
| } |
| /* Else fall through to one of the other strategies... */ |
| case ASB_DISCARD_OLDER_PRI: |
| if (self == 0 && peer == 1) { |
| rv = 1; |
| break; |
| } |
| if (self == 1 && peer == 0) { |
| rv = -1; |
| break; |
| } |
| /* Else fall through to one of the other strategies... */ |
| drbd_warn(device, "Discard younger/older primary did not find a decision\n" |
| "Using discard-least-changes instead\n"); |
| case ASB_DISCARD_ZERO_CHG: |
| if (ch_peer == 0 && ch_self == 0) { |
| rv = test_bit(RESOLVE_CONFLICTS, &peer_device->connection->flags) |
| ? -1 : 1; |
| break; |
| } else { |
| if (ch_peer == 0) { rv = 1; break; } |
| if (ch_self == 0) { rv = -1; break; } |
| } |
| if (after_sb_0p == ASB_DISCARD_ZERO_CHG) |
| break; |
| case ASB_DISCARD_LEAST_CHG: |
| if (ch_self < ch_peer) |
| rv = -1; |
| else if (ch_self > ch_peer) |
| rv = 1; |
| else /* ( ch_self == ch_peer ) */ |
| /* Well, then use something else. */ |
| rv = test_bit(RESOLVE_CONFLICTS, &peer_device->connection->flags) |
| ? -1 : 1; |
| break; |
| case ASB_DISCARD_LOCAL: |
| rv = -1; |
| break; |
| case ASB_DISCARD_REMOTE: |
| rv = 1; |
| } |
| |
| return rv; |
| } |
| |
| /** |
| * drbd_asb_recover_1p - Recover after split-brain with one remaining primary |
| */ |
| static int drbd_asb_recover_1p(struct drbd_peer_device *peer_device) __must_hold(local) |
| { |
| struct drbd_device *device = peer_device->device; |
| int hg, rv = -100; |
| enum drbd_after_sb_p after_sb_1p; |
| |
| rcu_read_lock(); |
| after_sb_1p = rcu_dereference(peer_device->connection->net_conf)->after_sb_1p; |
| rcu_read_unlock(); |
| switch (after_sb_1p) { |
| case ASB_DISCARD_YOUNGER_PRI: |
| case ASB_DISCARD_OLDER_PRI: |
| case ASB_DISCARD_LEAST_CHG: |
| case ASB_DISCARD_LOCAL: |
| case ASB_DISCARD_REMOTE: |
| case ASB_DISCARD_ZERO_CHG: |
| drbd_err(device, "Configuration error.\n"); |
| break; |
| case ASB_DISCONNECT: |
| break; |
| case ASB_CONSENSUS: |
| hg = drbd_asb_recover_0p(peer_device); |
| if (hg == -1 && device->state.role == R_SECONDARY) |
| rv = hg; |
| if (hg == 1 && device->state.role == R_PRIMARY) |
| rv = hg; |
| break; |
| case ASB_VIOLENTLY: |
| rv = drbd_asb_recover_0p(peer_device); |
| break; |
| case ASB_DISCARD_SECONDARY: |
| return device->state.role == R_PRIMARY ? 1 : -1; |
| case ASB_CALL_HELPER: |
| hg = drbd_asb_recover_0p(peer_device); |
| if (hg == -1 && device->state.role == R_PRIMARY) { |
| enum drbd_state_rv rv2; |
| |
| /* drbd_change_state() does not sleep while in SS_IN_TRANSIENT_STATE, |
| * we might be here in C_WF_REPORT_PARAMS which is transient. |
| * we do not need to wait for the after state change work either. */ |
| rv2 = drbd_change_state(device, CS_VERBOSE, NS(role, R_SECONDARY)); |
| if (rv2 != SS_SUCCESS) { |
| drbd_khelper(device, "pri-lost-after-sb"); |
| } else { |
| drbd_warn(device, "Successfully gave up primary role.\n"); |
| rv = hg; |
| } |
| } else |
| rv = hg; |
| } |
| |
| return rv; |
| } |
| |
| /** |
| * drbd_asb_recover_2p - Recover after split-brain with two remaining primaries |
| */ |
| static int drbd_asb_recover_2p(struct drbd_peer_device *peer_device) __must_hold(local) |
| { |
| struct drbd_device *device = peer_device->device; |
| int hg, rv = -100; |
| enum drbd_after_sb_p after_sb_2p; |
| |
| rcu_read_lock(); |
| after_sb_2p = rcu_dereference(peer_device->connection->net_conf)->after_sb_2p; |
| rcu_read_unlock(); |
| switch (after_sb_2p) { |
| case ASB_DISCARD_YOUNGER_PRI: |
| case ASB_DISCARD_OLDER_PRI: |
| case ASB_DISCARD_LEAST_CHG: |
| case ASB_DISCARD_LOCAL: |
| case ASB_DISCARD_REMOTE: |
| case ASB_CONSENSUS: |
| case ASB_DISCARD_SECONDARY: |
| case ASB_DISCARD_ZERO_CHG: |
| drbd_err(device, "Configuration error.\n"); |
| break; |
| case ASB_VIOLENTLY: |
| rv = drbd_asb_recover_0p(peer_device); |
| break; |
| case ASB_DISCONNECT: |
| break; |
| case ASB_CALL_HELPER: |
| hg = drbd_asb_recover_0p(peer_device); |
| if (hg == -1) { |
| enum drbd_state_rv rv2; |
| |
| /* drbd_change_state() does not sleep while in SS_IN_TRANSIENT_STATE, |
| * we might be here in C_WF_REPORT_PARAMS which is transient. |
| * we do not need to wait for the after state change work either. */ |
| rv2 = drbd_change_state(device, CS_VERBOSE, NS(role, R_SECONDARY)); |
| if (rv2 != SS_SUCCESS) { |
| drbd_khelper(device, "pri-lost-after-sb"); |
| } else { |
| drbd_warn(device, "Successfully gave up primary role.\n"); |
| rv = hg; |
| } |
| } else |
| rv = hg; |
| } |
| |
| return rv; |
| } |
| |
| static void drbd_uuid_dump(struct drbd_device *device, char *text, u64 *uuid, |
| u64 bits, u64 flags) |
| { |
| if (!uuid) { |
| drbd_info(device, "%s uuid info vanished while I was looking!\n", text); |
| return; |
| } |
| drbd_info(device, "%s %016llX:%016llX:%016llX:%016llX bits:%llu flags:%llX\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], |
| (unsigned long long)bits, |
| (unsigned long long)flags); |
| } |
| |
| /* |
| 100 after split brain try auto recover |
| 2 C_SYNC_SOURCE set BitMap |
| 1 C_SYNC_SOURCE use BitMap |
| 0 no Sync |
| -1 C_SYNC_TARGET use BitMap |
| -2 C_SYNC_TARGET set BitMap |
| -100 after split brain, disconnect |
| -1000 unrelated data |
| -1091 requires proto 91 |
| -1096 requires proto 96 |
| */ |
| static int drbd_uuid_compare(struct drbd_device *const device, int *rule_nr) __must_hold(local) |
| { |
| struct drbd_peer_device *const peer_device = first_peer_device(device); |
| struct drbd_connection *const connection = peer_device ? peer_device->connection : NULL; |
| u64 self, peer; |
| int i, j; |
| |
| self = device->ldev->md.uuid[UI_CURRENT] & ~((u64)1); |
| peer = device->p_uuid[UI_CURRENT] & ~((u64)1); |
| |
| *rule_nr = 10; |
| if (self == UUID_JUST_CREATED && peer == UUID_JUST_CREATED) |
| return 0; |
| |
| *rule_nr = 20; |
| if ((self == UUID_JUST_CREATED || self == (u64)0) && |
| peer != UUID_JUST_CREATED) |
| return -2; |
| |
| *rule_nr = 30; |
| if (self != UUID_JUST_CREATED && |
| (peer == UUID_JUST_CREATED || peer == (u64)0)) |
| return 2; |
| |
| if (self == peer) { |
| int rct, dc; /* roles at crash time */ |
| |
| if (device->p_uuid[UI_BITMAP] == (u64)0 && device->ldev->md.uuid[UI_BITMAP] != (u64)0) { |
| |
| if (connection->agreed_pro_version < 91) |
| return -1091; |
| |
| if ((device->ldev->md.uuid[UI_BITMAP] & ~((u64)1)) == (device->p_uuid[UI_HISTORY_START] & ~((u64)1)) && |
| (device->ldev->md.uuid[UI_HISTORY_START] & ~((u64)1)) == (device->p_uuid[UI_HISTORY_START + 1] & ~((u64)1))) { |
| drbd_info(device, "was SyncSource, missed the resync finished event, corrected myself:\n"); |
| 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; |
| |
| drbd_uuid_dump(device, "self", device->ldev->md.uuid, |
| device->state.disk >= D_NEGOTIATING ? drbd_bm_total_weight(device) : 0, 0); |
| *rule_nr = 34; |
| } else { |
| drbd_info(device, "was SyncSource (peer failed to write sync_uuid)\n"); |
| *rule_nr = 36; |
| } |
| |
| return 1; |
| } |
| |
| if (device->ldev->md.uuid[UI_BITMAP] == (u64)0 && device->p_uuid[UI_BITMAP] != (u64)0) { |
| |
| if (connection->agreed_pro_version < 91) |
| return -1091; |
| |
| if ((device->ldev->md.uuid[UI_HISTORY_START] & ~((u64)1)) == (device->p_uuid[UI_BITMAP] & ~((u64)1)) && |
| (device->ldev->md.uuid[UI_HISTORY_START + 1] & ~((u64)1)) == (device->p_uuid[UI_HISTORY_START] & |