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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/block/drbd/drbd_receiver.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/block/drbd/drbd_receiver.c')
-rw-r--r--kernel/drivers/block/drbd/drbd_receiver.c5661
1 files changed, 5661 insertions, 0 deletions
diff --git a/kernel/drivers/block/drbd/drbd_receiver.c b/kernel/drivers/block/drbd/drbd_receiver.c
new file mode 100644
index 000000000..cee20354a
--- /dev/null
+++ b/kernel/drivers/block/drbd/drbd_receiver.c
@@ -0,0 +1,5661 @@
+/*
+ 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, (gfp_mask & __GFP_WAIT));
+ 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(((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(((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] & ~((u64)1))) {
+ drbd_info(device, "was SyncTarget, peer missed the resync finished event, corrected peer:\n");
+
+ device->p_uuid[UI_HISTORY_START + 1] = device->p_uuid[UI_HISTORY_START];
+ device->p_uuid[UI_HISTORY_START] = device->p_uuid[UI_BITMAP];
+ device->p_uuid[UI_BITMAP] = 0UL;
+
+ drbd_uuid_dump(device, "peer", device->p_uuid, device->p_uuid[UI_SIZE], device->p_uuid[UI_FLAGS]);
+ *rule_nr = 35;
+ } else {
+ drbd_info(device, "was SyncTarget (failed to write sync_uuid)\n");
+ *rule_nr = 37;
+ }
+
+ return -1;
+ }
+
+ /* Common power [off|failure] */
+ rct = (test_bit(CRASHED_PRIMARY, &device->flags) ? 1 : 0) +
+ (device->p_uuid[UI_FLAGS] & 2);
+ /* lowest bit is set when we were primary,
+ * next bit (weight 2) is set when peer was primary */
+ *rule_nr = 40;
+
+ switch (rct) {
+ case 0: /* !self_pri && !peer_pri */ return 0;
+ case 1: /* self_pri && !peer_pri */ return 1;
+ case 2: /* !self_pri && peer_pri */ return -1;
+ case 3: /* self_pri && peer_pri */
+ dc = test_bit(RESOLVE_CONFLICTS, &connection->flags);
+ return dc ? -1 : 1;
+ }
+ }
+
+ *rule_nr = 50;
+ peer = device->p_uuid[UI_BITMAP] & ~((u64)1);
+ if (self == peer)
+ return -1;
+
+ *rule_nr = 51;
+ peer = device->p_uuid[UI_HISTORY_START] & ~((u64)1);
+ if (self == peer) {
+ if (connection->agreed_pro_version < 96 ?
+ (device->ldev->md.uuid[UI_HISTORY_START] & ~((u64)1)) ==
+ (device->p_uuid[UI_HISTORY_START + 1] & ~((u64)1)) :
+ peer + UUID_NEW_BM_OFFSET == (device->p_uuid[UI_BITMAP] & ~((u64)1))) {
+ /* The last P_SYNC_UUID did not get though. Undo the last start of
+ resync as sync source modifications of the peer's UUIDs. */
+
+ if (connection->agreed_pro_version < 91)
+ return -1091;
+
+ device->p_uuid[UI_BITMAP] = device->p_uuid[UI_HISTORY_START];
+ device->p_uuid[UI_HISTORY_START] = device->p_uuid[UI_HISTORY_START + 1];
+
+ drbd_info(device, "Lost last syncUUID packet, corrected:\n");
+ drbd_uuid_dump(device, "peer", device->p_uuid, device->p_uuid[UI_SIZE], device->p_uuid[UI_FLAGS]);
+
+ return -1;
+ }
+ }
+
+ *rule_nr = 60;
+ self = device->ldev->md.uuid[UI_CURRENT] & ~((u64)1);
+ for (i = UI_HISTORY_START; i <= UI_HISTORY_END; i++) {
+ peer = device->p_uuid[i] & ~((u64)1);
+ if (self == peer)
+ return -2;
+ }
+
+ *rule_nr = 70;
+ self = device->ldev->md.uuid[UI_BITMAP] & ~((u64)1);
+ peer = device->p_uuid[UI_CURRENT] & ~((u64)1);
+ if (self == peer)
+ return 1;
+
+ *rule_nr = 71;
+ self = device->ldev->md.uuid[UI_HISTORY_START] & ~((u64)1);
+ if (self == peer) {
+ if (connection->agreed_pro_version < 96 ?
+ (device->ldev->md.uuid[UI_HISTORY_START + 1] & ~((u64)1)) ==
+ (device->p_uuid[UI_HISTORY_START] & ~((u64)1)) :
+ self + UUID_NEW_BM_OFFSET == (device->ldev->md.uuid[UI_BITMAP] & ~((u64)1))) {
+ /* The last P_SYNC_UUID did not get though. Undo the last start of
+ resync as sync source modifications of our UUIDs. */
+
+ if (connection->agreed_pro_version < 91)
+ return -1091;
+
+ __drbd_uuid_set(device, UI_BITMAP, device->ldev->md.uuid[UI_HISTORY_START]);
+ __drbd_uuid_set(device, UI_HISTORY_START, device->ldev->md.uuid[UI_HISTORY_START + 1]);
+
+ drbd_info(device, "Last syncUUID did not get through, corrected:\n");
+ drbd_uuid_dump(device, "self", device->ldev->md.uuid,
+ device->state.disk >= D_NEGOTIATING ? drbd_bm_total_weight(device) : 0, 0);
+
+ return 1;
+ }
+ }
+
+
+ *rule_nr = 80;
+ peer = device->p_uuid[UI_CURRENT] & ~((u64)1);
+ for (i = UI_HISTORY_START; i <= UI_HISTORY_END; i++) {
+ self = device->ldev->md.uuid[i] & ~((u64)1);
+ if (self == peer)
+ return 2;
+ }
+
+ *rule_nr = 90;
+ self = device->ldev->md.uuid[UI_BITMAP] & ~((u64)1);
+ peer = device->p_uuid[UI_BITMAP] & ~((u64)1);
+ if (self == peer && self != ((u64)0))
+ return 100;
+
+ *rule_nr = 100;
+ for (i = UI_HISTORY_START; i <= UI_HISTORY_END; i++) {
+ self = device->ldev->md.uuid[i] & ~((u64)1);
+ for (j = UI_HISTORY_START; j <= UI_HISTORY_END; j++) {
+ peer = device->p_uuid[j] & ~((u64)1);
+ if (self == peer)
+ return -100;
+ }
+ }
+
+ return -1000;
+}
+
+/* drbd_sync_handshake() returns the new conn state on success, or
+ CONN_MASK (-1) on failure.
+ */
+static enum drbd_conns drbd_sync_handshake(struct drbd_peer_device *peer_device,
+ enum drbd_role peer_role,
+ enum drbd_disk_state peer_disk) __must_hold(local)
+{
+ struct drbd_device *device = peer_device->device;
+ enum drbd_conns rv = C_MASK;
+ enum drbd_disk_state mydisk;
+ struct net_conf *nc;
+ int hg, rule_nr, rr_conflict, tentative;
+
+ mydisk = device->state.disk;
+ if (mydisk == D_NEGOTIATING)
+ mydisk = device->new_state_tmp.disk;
+
+ drbd_info(device, "drbd_sync_handshake:\n");
+
+ spin_lock_irq(&device->ldev->md.uuid_lock);
+ drbd_uuid_dump(device, "self", device->ldev->md.uuid, device->comm_bm_set, 0);
+ drbd_uuid_dump(device, "peer", device->p_uuid,
+ device->p_uuid[UI_SIZE], device->p_uuid[UI_FLAGS]);
+
+ hg = drbd_uuid_compare(device, &rule_nr);
+ spin_unlock_irq(&device->ldev->md.uuid_lock);
+
+ drbd_info(device, "uuid_compare()=%d by rule %d\n", hg, rule_nr);
+
+ if (hg == -1000) {
+ drbd_alert(device, "Unrelated data, aborting!\n");
+ return C_MASK;
+ }
+ if (hg < -1000) {
+ drbd_alert(device, "To resolve this both sides have to support at least protocol %d\n", -hg - 1000);
+ return C_MASK;
+ }
+
+ if ((mydisk == D_INCONSISTENT && peer_disk > D_INCONSISTENT) ||
+ (peer_disk == D_INCONSISTENT && mydisk > D_INCONSISTENT)) {
+ int f = (hg == -100) || abs(hg) == 2;
+ hg = mydisk > D_INCONSISTENT ? 1 : -1;
+ if (f)
+ hg = hg*2;
+ drbd_info(device, "Becoming sync %s due to disk states.\n",
+ hg > 0 ? "source" : "target");
+ }
+
+ if (abs(hg) == 100)
+ drbd_khelper(device, "initial-split-brain");
+
+ rcu_read_lock();
+ nc = rcu_dereference(peer_device->connection->net_conf);
+
+ if (hg == 100 || (hg == -100 && nc->always_asbp)) {
+ int pcount = (device->state.role == R_PRIMARY)
+ + (peer_role == R_PRIMARY);
+ int forced = (hg == -100);
+
+ switch (pcount) {
+ case 0:
+ hg = drbd_asb_recover_0p(peer_device);
+ break;
+ case 1:
+ hg = drbd_asb_recover_1p(peer_device);
+ break;
+ case 2:
+ hg = drbd_asb_recover_2p(peer_device);
+ break;
+ }
+ if (abs(hg) < 100) {
+ drbd_warn(device, "Split-Brain detected, %d primaries, "
+ "automatically solved. Sync from %s node\n",
+ pcount, (hg < 0) ? "peer" : "this");
+ if (forced) {
+ drbd_warn(device, "Doing a full sync, since"
+ " UUIDs where ambiguous.\n");
+ hg = hg*2;
+ }
+ }
+ }
+
+ if (hg == -100) {
+ if (test_bit(DISCARD_MY_DATA, &device->flags) && !(device->p_uuid[UI_FLAGS]&1))
+ hg = -1;
+ if (!test_bit(DISCARD_MY_DATA, &device->flags) && (device->p_uuid[UI_FLAGS]&1))
+ hg = 1;
+
+ if (abs(hg) < 100)
+ drbd_warn(device, "Split-Brain detected, manually solved. "
+ "Sync from %s node\n",
+ (hg < 0) ? "peer" : "this");
+ }
+ rr_conflict = nc->rr_conflict;
+ tentative = nc->tentative;
+ rcu_read_unlock();
+
+ if (hg == -100) {
+ /* FIXME this log message is not correct if we end up here
+ * after an attempted attach on a diskless node.
+ * We just refuse to attach -- well, we drop the "connection"
+ * to that disk, in a way... */
+ drbd_alert(device, "Split-Brain detected but unresolved, dropping connection!\n");
+ drbd_khelper(device, "split-brain");
+ return C_MASK;
+ }
+
+ if (hg > 0 && mydisk <= D_INCONSISTENT) {
+ drbd_err(device, "I shall become SyncSource, but I am inconsistent!\n");
+ return C_MASK;
+ }
+
+ if (hg < 0 && /* by intention we do not use mydisk here. */
+ device->state.role == R_PRIMARY && device->state.disk >= D_CONSISTENT) {
+ switch (rr_conflict) {
+ case ASB_CALL_HELPER:
+ drbd_khelper(device, "pri-lost");
+ /* fall through */
+ case ASB_DISCONNECT:
+ drbd_err(device, "I shall become SyncTarget, but I am primary!\n");
+ return C_MASK;
+ case ASB_VIOLENTLY:
+ drbd_warn(device, "Becoming SyncTarget, violating the stable-data"
+ "assumption\n");
+ }
+ }
+
+ if (tentative || test_bit(CONN_DRY_RUN, &peer_device->connection->flags)) {
+ if (hg == 0)
+ drbd_info(device, "dry-run connect: No resync, would become Connected immediately.\n");
+ else
+ drbd_info(device, "dry-run connect: Would become %s, doing a %s resync.",
+ drbd_conn_str(hg > 0 ? C_SYNC_SOURCE : C_SYNC_TARGET),
+ abs(hg) >= 2 ? "full" : "bit-map based");
+ return C_MASK;
+ }
+
+ if (abs(hg) >= 2) {
+ drbd_info(device, "Writing the whole bitmap, full sync required after drbd_sync_handshake.\n");
+ if (drbd_bitmap_io(device, &drbd_bmio_set_n_write, "set_n_write from sync_handshake",
+ BM_LOCKED_SET_ALLOWED))
+ return C_MASK;
+ }
+
+ if (hg > 0) { /* become sync source. */
+ rv = C_WF_BITMAP_S;
+ } else if (hg < 0) { /* become sync target */
+ rv = C_WF_BITMAP_T;
+ } else {
+ rv = C_CONNECTED;
+ if (drbd_bm_total_weight(device)) {
+ drbd_info(device, "No resync, but %lu bits in bitmap!\n",
+ drbd_bm_total_weight(device));
+ }
+ }
+
+ return rv;
+}
+
+static enum drbd_after_sb_p convert_after_sb(enum drbd_after_sb_p peer)
+{
+ /* ASB_DISCARD_REMOTE - ASB_DISCARD_LOCAL is valid */
+ if (peer == ASB_DISCARD_REMOTE)
+ return ASB_DISCARD_LOCAL;
+
+ /* any other things with ASB_DISCARD_REMOTE or ASB_DISCARD_LOCAL are invalid */
+ if (peer == ASB_DISCARD_LOCAL)
+ return ASB_DISCARD_REMOTE;
+
+ /* everything else is valid if they are equal on both sides. */
+ return peer;
+}
+
+static int receive_protocol(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct p_protocol *p = pi->data;
+ enum drbd_after_sb_p p_after_sb_0p, p_after_sb_1p, p_after_sb_2p;
+ int p_proto, p_discard_my_data, p_two_primaries, cf;
+ struct net_conf *nc, *old_net_conf, *new_net_conf = NULL;
+ char integrity_alg[SHARED_SECRET_MAX] = "";
+ struct crypto_hash *peer_integrity_tfm = NULL;
+ void *int_dig_in = NULL, *int_dig_vv = NULL;
+
+ p_proto = be32_to_cpu(p->protocol);
+ p_after_sb_0p = be32_to_cpu(p->after_sb_0p);
+ p_after_sb_1p = be32_to_cpu(p->after_sb_1p);
+ p_after_sb_2p = be32_to_cpu(p->after_sb_2p);
+ p_two_primaries = be32_to_cpu(p->two_primaries);
+ cf = be32_to_cpu(p->conn_flags);
+ p_discard_my_data = cf & CF_DISCARD_MY_DATA;
+
+ if (connection->agreed_pro_version >= 87) {
+ int err;
+
+ if (pi->size > sizeof(integrity_alg))
+ return -EIO;
+ err = drbd_recv_all(connection, integrity_alg, pi->size);
+ if (err)
+ return err;
+ integrity_alg[SHARED_SECRET_MAX - 1] = 0;
+ }
+
+ if (pi->cmd != P_PROTOCOL_UPDATE) {
+ clear_bit(CONN_DRY_RUN, &connection->flags);
+
+ if (cf & CF_DRY_RUN)
+ set_bit(CONN_DRY_RUN, &connection->flags);
+
+ rcu_read_lock();
+ nc = rcu_dereference(connection->net_conf);
+
+ if (p_proto != nc->wire_protocol) {
+ drbd_err(connection, "incompatible %s settings\n", "protocol");
+ goto disconnect_rcu_unlock;
+ }
+
+ if (convert_after_sb(p_after_sb_0p) != nc->after_sb_0p) {
+ drbd_err(connection, "incompatible %s settings\n", "after-sb-0pri");
+ goto disconnect_rcu_unlock;
+ }
+
+ if (convert_after_sb(p_after_sb_1p) != nc->after_sb_1p) {
+ drbd_err(connection, "incompatible %s settings\n", "after-sb-1pri");
+ goto disconnect_rcu_unlock;
+ }
+
+ if (convert_after_sb(p_after_sb_2p) != nc->after_sb_2p) {
+ drbd_err(connection, "incompatible %s settings\n", "after-sb-2pri");
+ goto disconnect_rcu_unlock;
+ }
+
+ if (p_discard_my_data && nc->discard_my_data) {
+ drbd_err(connection, "incompatible %s settings\n", "discard-my-data");
+ goto disconnect_rcu_unlock;
+ }
+
+ if (p_two_primaries != nc->two_primaries) {
+ drbd_err(connection, "incompatible %s settings\n", "allow-two-primaries");
+ goto disconnect_rcu_unlock;
+ }
+
+ if (strcmp(integrity_alg, nc->integrity_alg)) {
+ drbd_err(connection, "incompatible %s settings\n", "data-integrity-alg");
+ goto disconnect_rcu_unlock;
+ }
+
+ rcu_read_unlock();
+ }
+
+ if (integrity_alg[0]) {
+ int hash_size;
+
+ /*
+ * We can only change the peer data integrity algorithm
+ * here. Changing our own data integrity algorithm
+ * requires that we send a P_PROTOCOL_UPDATE packet at
+ * the same time; otherwise, the peer has no way to
+ * tell between which packets the algorithm should
+ * change.
+ */
+
+ peer_integrity_tfm = crypto_alloc_hash(integrity_alg, 0, CRYPTO_ALG_ASYNC);
+ if (!peer_integrity_tfm) {
+ drbd_err(connection, "peer data-integrity-alg %s not supported\n",
+ integrity_alg);
+ goto disconnect;
+ }
+
+ hash_size = crypto_hash_digestsize(peer_integrity_tfm);
+ int_dig_in = kmalloc(hash_size, GFP_KERNEL);
+ int_dig_vv = kmalloc(hash_size, GFP_KERNEL);
+ if (!(int_dig_in && int_dig_vv)) {
+ drbd_err(connection, "Allocation of buffers for data integrity checking failed\n");
+ goto disconnect;
+ }
+ }
+
+ new_net_conf = kmalloc(sizeof(struct net_conf), GFP_KERNEL);
+ if (!new_net_conf) {
+ drbd_err(connection, "Allocation of new net_conf failed\n");
+ goto disconnect;
+ }
+
+ mutex_lock(&connection->data.mutex);
+ mutex_lock(&connection->resource->conf_update);
+ old_net_conf = connection->net_conf;
+ *new_net_conf = *old_net_conf;
+
+ new_net_conf->wire_protocol = p_proto;
+ new_net_conf->after_sb_0p = convert_after_sb(p_after_sb_0p);
+ new_net_conf->after_sb_1p = convert_after_sb(p_after_sb_1p);
+ new_net_conf->after_sb_2p = convert_after_sb(p_after_sb_2p);
+ new_net_conf->two_primaries = p_two_primaries;
+
+ rcu_assign_pointer(connection->net_conf, new_net_conf);
+ mutex_unlock(&connection->resource->conf_update);
+ mutex_unlock(&connection->data.mutex);
+
+ crypto_free_hash(connection->peer_integrity_tfm);
+ kfree(connection->int_dig_in);
+ kfree(connection->int_dig_vv);
+ connection->peer_integrity_tfm = peer_integrity_tfm;
+ connection->int_dig_in = int_dig_in;
+ connection->int_dig_vv = int_dig_vv;
+
+ if (strcmp(old_net_conf->integrity_alg, integrity_alg))
+ drbd_info(connection, "peer data-integrity-alg: %s\n",
+ integrity_alg[0] ? integrity_alg : "(none)");
+
+ synchronize_rcu();
+ kfree(old_net_conf);
+ return 0;
+
+disconnect_rcu_unlock:
+ rcu_read_unlock();
+disconnect:
+ crypto_free_hash(peer_integrity_tfm);
+ kfree(int_dig_in);
+ kfree(int_dig_vv);
+ conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_HARD);
+ return -EIO;
+}
+
+/* helper function
+ * input: alg name, feature name
+ * return: NULL (alg name was "")
+ * ERR_PTR(error) if something goes wrong
+ * or the crypto hash ptr, if it worked out ok. */
+static struct crypto_hash *drbd_crypto_alloc_digest_safe(const struct drbd_device *device,
+ const char *alg, const char *name)
+{
+ struct crypto_hash *tfm;
+
+ if (!alg[0])
+ return NULL;
+
+ tfm = crypto_alloc_hash(alg, 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(tfm)) {
+ drbd_err(device, "Can not allocate \"%s\" as %s (reason: %ld)\n",
+ alg, name, PTR_ERR(tfm));
+ return tfm;
+ }
+ return tfm;
+}
+
+static int ignore_remaining_packet(struct drbd_connection *connection, struct packet_info *pi)
+{
+ void *buffer = connection->data.rbuf;
+ int size = pi->size;
+
+ while (size) {
+ int s = min_t(int, size, DRBD_SOCKET_BUFFER_SIZE);
+ s = drbd_recv(connection, buffer, s);
+ if (s <= 0) {
+ if (s < 0)
+ return s;
+ break;
+ }
+ size -= s;
+ }
+ if (size)
+ return -EIO;
+ return 0;
+}
+
+/*
+ * config_unknown_volume - device configuration command for unknown volume
+ *
+ * When a device is added to an existing connection, the node on which the
+ * device is added first will send configuration commands to its peer but the
+ * peer will not know about the device yet. It will warn and ignore these
+ * commands. Once the device is added on the second node, the second node will
+ * send the same device configuration commands, but in the other direction.
+ *
+ * (We can also end up here if drbd is misconfigured.)
+ */
+static int config_unknown_volume(struct drbd_connection *connection, struct packet_info *pi)
+{
+ drbd_warn(connection, "%s packet received for volume %u, which is not configured locally\n",
+ cmdname(pi->cmd), pi->vnr);
+ return ignore_remaining_packet(connection, pi);
+}
+
+static int receive_SyncParam(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct drbd_peer_device *peer_device;
+ struct drbd_device *device;
+ struct p_rs_param_95 *p;
+ unsigned int header_size, data_size, exp_max_sz;
+ struct crypto_hash *verify_tfm = NULL;
+ struct crypto_hash *csums_tfm = NULL;
+ struct net_conf *old_net_conf, *new_net_conf = NULL;
+ struct disk_conf *old_disk_conf = NULL, *new_disk_conf = NULL;
+ const int apv = connection->agreed_pro_version;
+ struct fifo_buffer *old_plan = NULL, *new_plan = NULL;
+ int fifo_size = 0;
+ int err;
+
+ peer_device = conn_peer_device(connection, pi->vnr);
+ if (!peer_device)
+ return config_unknown_volume(connection, pi);
+ device = peer_device->device;
+
+ exp_max_sz = apv <= 87 ? sizeof(struct p_rs_param)
+ : apv == 88 ? sizeof(struct p_rs_param)
+ + SHARED_SECRET_MAX
+ : apv <= 94 ? sizeof(struct p_rs_param_89)
+ : /* apv >= 95 */ sizeof(struct p_rs_param_95);
+
+ if (pi->size > exp_max_sz) {
+ drbd_err(device, "SyncParam packet too long: received %u, expected <= %u bytes\n",
+ pi->size, exp_max_sz);
+ return -EIO;
+ }
+
+ if (apv <= 88) {
+ header_size = sizeof(struct p_rs_param);
+ data_size = pi->size - header_size;
+ } else if (apv <= 94) {
+ header_size = sizeof(struct p_rs_param_89);
+ data_size = pi->size - header_size;
+ D_ASSERT(device, data_size == 0);
+ } else {
+ header_size = sizeof(struct p_rs_param_95);
+ data_size = pi->size - header_size;
+ D_ASSERT(device, data_size == 0);
+ }
+
+ /* initialize verify_alg and csums_alg */
+ p = pi->data;
+ memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX);
+
+ err = drbd_recv_all(peer_device->connection, p, header_size);
+ if (err)
+ return err;
+
+ mutex_lock(&connection->resource->conf_update);
+ old_net_conf = peer_device->connection->net_conf;
+ if (get_ldev(device)) {
+ new_disk_conf = kzalloc(sizeof(struct disk_conf), GFP_KERNEL);
+ if (!new_disk_conf) {
+ put_ldev(device);
+ mutex_unlock(&connection->resource->conf_update);
+ drbd_err(device, "Allocation of new disk_conf failed\n");
+ return -ENOMEM;
+ }
+
+ old_disk_conf = device->ldev->disk_conf;
+ *new_disk_conf = *old_disk_conf;
+
+ new_disk_conf->resync_rate = be32_to_cpu(p->resync_rate);
+ }
+
+ if (apv >= 88) {
+ if (apv == 88) {
+ if (data_size > SHARED_SECRET_MAX || data_size == 0) {
+ drbd_err(device, "verify-alg of wrong size, "
+ "peer wants %u, accepting only up to %u byte\n",
+ data_size, SHARED_SECRET_MAX);
+ err = -EIO;
+ goto reconnect;
+ }
+
+ err = drbd_recv_all(peer_device->connection, p->verify_alg, data_size);
+ if (err)
+ goto reconnect;
+ /* we expect NUL terminated string */
+ /* but just in case someone tries to be evil */
+ D_ASSERT(device, p->verify_alg[data_size-1] == 0);
+ p->verify_alg[data_size-1] = 0;
+
+ } else /* apv >= 89 */ {
+ /* we still expect NUL terminated strings */
+ /* but just in case someone tries to be evil */
+ D_ASSERT(device, p->verify_alg[SHARED_SECRET_MAX-1] == 0);
+ D_ASSERT(device, p->csums_alg[SHARED_SECRET_MAX-1] == 0);
+ p->verify_alg[SHARED_SECRET_MAX-1] = 0;
+ p->csums_alg[SHARED_SECRET_MAX-1] = 0;
+ }
+
+ if (strcmp(old_net_conf->verify_alg, p->verify_alg)) {
+ if (device->state.conn == C_WF_REPORT_PARAMS) {
+ drbd_err(device, "Different verify-alg settings. me=\"%s\" peer=\"%s\"\n",
+ old_net_conf->verify_alg, p->verify_alg);
+ goto disconnect;
+ }
+ verify_tfm = drbd_crypto_alloc_digest_safe(device,
+ p->verify_alg, "verify-alg");
+ if (IS_ERR(verify_tfm)) {
+ verify_tfm = NULL;
+ goto disconnect;
+ }
+ }
+
+ if (apv >= 89 && strcmp(old_net_conf->csums_alg, p->csums_alg)) {
+ if (device->state.conn == C_WF_REPORT_PARAMS) {
+ drbd_err(device, "Different csums-alg settings. me=\"%s\" peer=\"%s\"\n",
+ old_net_conf->csums_alg, p->csums_alg);
+ goto disconnect;
+ }
+ csums_tfm = drbd_crypto_alloc_digest_safe(device,
+ p->csums_alg, "csums-alg");
+ if (IS_ERR(csums_tfm)) {
+ csums_tfm = NULL;
+ goto disconnect;
+ }
+ }
+
+ if (apv > 94 && new_disk_conf) {
+ new_disk_conf->c_plan_ahead = be32_to_cpu(p->c_plan_ahead);
+ new_disk_conf->c_delay_target = be32_to_cpu(p->c_delay_target);
+ new_disk_conf->c_fill_target = be32_to_cpu(p->c_fill_target);
+ new_disk_conf->c_max_rate = be32_to_cpu(p->c_max_rate);
+
+ fifo_size = (new_disk_conf->c_plan_ahead * 10 * SLEEP_TIME) / HZ;
+ if (fifo_size != device->rs_plan_s->size) {
+ new_plan = fifo_alloc(fifo_size);
+ if (!new_plan) {
+ drbd_err(device, "kmalloc of fifo_buffer failed");
+ put_ldev(device);
+ goto disconnect;
+ }
+ }
+ }
+
+ if (verify_tfm || csums_tfm) {
+ new_net_conf = kzalloc(sizeof(struct net_conf), GFP_KERNEL);
+ if (!new_net_conf) {
+ drbd_err(device, "Allocation of new net_conf failed\n");
+ goto disconnect;
+ }
+
+ *new_net_conf = *old_net_conf;
+
+ if (verify_tfm) {
+ strcpy(new_net_conf->verify_alg, p->verify_alg);
+ new_net_conf->verify_alg_len = strlen(p->verify_alg) + 1;
+ crypto_free_hash(peer_device->connection->verify_tfm);
+ peer_device->connection->verify_tfm = verify_tfm;
+ drbd_info(device, "using verify-alg: \"%s\"\n", p->verify_alg);
+ }
+ if (csums_tfm) {
+ strcpy(new_net_conf->csums_alg, p->csums_alg);
+ new_net_conf->csums_alg_len = strlen(p->csums_alg) + 1;
+ crypto_free_hash(peer_device->connection->csums_tfm);
+ peer_device->connection->csums_tfm = csums_tfm;
+ drbd_info(device, "using csums-alg: \"%s\"\n", p->csums_alg);
+ }
+ rcu_assign_pointer(connection->net_conf, new_net_conf);
+ }
+ }
+
+ if (new_disk_conf) {
+ rcu_assign_pointer(device->ldev->disk_conf, new_disk_conf);
+ put_ldev(device);
+ }
+
+ if (new_plan) {
+ old_plan = device->rs_plan_s;
+ rcu_assign_pointer(device->rs_plan_s, new_plan);
+ }
+
+ mutex_unlock(&connection->resource->conf_update);
+ synchronize_rcu();
+ if (new_net_conf)
+ kfree(old_net_conf);
+ kfree(old_disk_conf);
+ kfree(old_plan);
+
+ return 0;
+
+reconnect:
+ if (new_disk_conf) {
+ put_ldev(device);
+ kfree(new_disk_conf);
+ }
+ mutex_unlock(&connection->resource->conf_update);
+ return -EIO;
+
+disconnect:
+ kfree(new_plan);
+ if (new_disk_conf) {
+ put_ldev(device);
+ kfree(new_disk_conf);
+ }
+ mutex_unlock(&connection->resource->conf_update);
+ /* just for completeness: actually not needed,
+ * as this is not reached if csums_tfm was ok. */
+ crypto_free_hash(csums_tfm);
+ /* but free the verify_tfm again, if csums_tfm did not work out */
+ crypto_free_hash(verify_tfm);
+ conn_request_state(peer_device->connection, NS(conn, C_DISCONNECTING), CS_HARD);
+ return -EIO;
+}
+
+/* warn if the arguments differ by more than 12.5% */
+static void warn_if_differ_considerably(struct drbd_device *device,
+ const char *s, sector_t a, sector_t b)
+{
+ sector_t d;
+ if (a == 0 || b == 0)
+ return;
+ d = (a > b) ? (a - b) : (b - a);
+ if (d > (a>>3) || d > (b>>3))
+ drbd_warn(device, "Considerable difference in %s: %llus vs. %llus\n", s,
+ (unsigned long long)a, (unsigned long long)b);
+}
+
+static int receive_sizes(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct drbd_peer_device *peer_device;
+ struct drbd_device *device;
+ struct p_sizes *p = pi->data;
+ enum determine_dev_size dd = DS_UNCHANGED;
+ sector_t p_size, p_usize, p_csize, my_usize;
+ int ldsc = 0; /* local disk size changed */
+ enum dds_flags ddsf;
+
+ peer_device = conn_peer_device(connection, pi->vnr);
+ if (!peer_device)
+ return config_unknown_volume(connection, pi);
+ device = peer_device->device;
+
+ p_size = be64_to_cpu(p->d_size);
+ p_usize = be64_to_cpu(p->u_size);
+ p_csize = be64_to_cpu(p->c_size);
+
+ /* just store the peer's disk size for now.
+ * we still need to figure out whether we accept that. */
+ device->p_size = p_size;
+
+ if (get_ldev(device)) {
+ rcu_read_lock();
+ my_usize = rcu_dereference(device->ldev->disk_conf)->disk_size;
+ rcu_read_unlock();
+
+ warn_if_differ_considerably(device, "lower level device sizes",
+ p_size, drbd_get_max_capacity(device->ldev));
+ warn_if_differ_considerably(device, "user requested size",
+ p_usize, my_usize);
+
+ /* if this is the first connect, or an otherwise expected
+ * param exchange, choose the minimum */
+ if (device->state.conn == C_WF_REPORT_PARAMS)
+ p_usize = min_not_zero(my_usize, p_usize);
+
+ /* Never shrink a device with usable data during connect.
+ But allow online shrinking if we are connected. */
+ if (drbd_new_dev_size(device, device->ldev, p_usize, 0) <
+ drbd_get_capacity(device->this_bdev) &&
+ device->state.disk >= D_OUTDATED &&
+ device->state.conn < C_CONNECTED) {
+ drbd_err(device, "The peer's disk size is too small!\n");
+ conn_request_state(peer_device->connection, NS(conn, C_DISCONNECTING), CS_HARD);
+ put_ldev(device);
+ return -EIO;
+ }
+
+ if (my_usize != p_usize) {
+ struct disk_conf *old_disk_conf, *new_disk_conf = NULL;
+
+ new_disk_conf = kzalloc(sizeof(struct disk_conf), GFP_KERNEL);
+ if (!new_disk_conf) {
+ drbd_err(device, "Allocation of new disk_conf failed\n");
+ put_ldev(device);
+ return -ENOMEM;
+ }
+
+ mutex_lock(&connection->resource->conf_update);
+ old_disk_conf = device->ldev->disk_conf;
+ *new_disk_conf = *old_disk_conf;
+ new_disk_conf->disk_size = p_usize;
+
+ rcu_assign_pointer(device->ldev->disk_conf, new_disk_conf);
+ mutex_unlock(&connection->resource->conf_update);
+ synchronize_rcu();
+ kfree(old_disk_conf);
+
+ drbd_info(device, "Peer sets u_size to %lu sectors\n",
+ (unsigned long)my_usize);
+ }
+
+ put_ldev(device);
+ }
+
+ device->peer_max_bio_size = be32_to_cpu(p->max_bio_size);
+ /* Leave drbd_reconsider_max_bio_size() before drbd_determine_dev_size().
+ In case we cleared the QUEUE_FLAG_DISCARD from our queue in
+ drbd_reconsider_max_bio_size(), we can be sure that after
+ drbd_determine_dev_size() no REQ_DISCARDs are in the queue. */
+
+ ddsf = be16_to_cpu(p->dds_flags);
+ if (get_ldev(device)) {
+ drbd_reconsider_max_bio_size(device, device->ldev);
+ dd = drbd_determine_dev_size(device, ddsf, NULL);
+ put_ldev(device);
+ if (dd == DS_ERROR)
+ return -EIO;
+ drbd_md_sync(device);
+ } else {
+ /*
+ * I am diskless, need to accept the peer's *current* size.
+ * I must NOT accept the peers backing disk size,
+ * it may have been larger than mine all along...
+ *
+ * At this point, the peer knows more about my disk, or at
+ * least about what we last agreed upon, than myself.
+ * So if his c_size is less than his d_size, the most likely
+ * reason is that *my* d_size was smaller last time we checked.
+ *
+ * However, if he sends a zero current size,
+ * take his (user-capped or) backing disk size anyways.
+ */
+ drbd_reconsider_max_bio_size(device, NULL);
+ drbd_set_my_capacity(device, p_csize ?: p_usize ?: p_size);
+ }
+
+ if (get_ldev(device)) {
+ if (device->ldev->known_size != drbd_get_capacity(device->ldev->backing_bdev)) {
+ device->ldev->known_size = drbd_get_capacity(device->ldev->backing_bdev);
+ ldsc = 1;
+ }
+
+ put_ldev(device);
+ }
+
+ if (device->state.conn > C_WF_REPORT_PARAMS) {
+ if (be64_to_cpu(p->c_size) !=
+ drbd_get_capacity(device->this_bdev) || ldsc) {
+ /* we have different sizes, probably peer
+ * needs to know my new size... */
+ drbd_send_sizes(peer_device, 0, ddsf);
+ }
+ if (test_and_clear_bit(RESIZE_PENDING, &device->flags) ||
+ (dd == DS_GREW && device->state.conn == C_CONNECTED)) {
+ if (device->state.pdsk >= D_INCONSISTENT &&
+ device->state.disk >= D_INCONSISTENT) {
+ if (ddsf & DDSF_NO_RESYNC)
+ drbd_info(device, "Resync of new storage suppressed with --assume-clean\n");
+ else
+ resync_after_online_grow(device);
+ } else
+ set_bit(RESYNC_AFTER_NEG, &device->flags);
+ }
+ }
+
+ return 0;
+}
+
+static int receive_uuids(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct drbd_peer_device *peer_device;
+ struct drbd_device *device;
+ struct p_uuids *p = pi->data;
+ u64 *p_uuid;
+ int i, updated_uuids = 0;
+
+ peer_device = conn_peer_device(connection, pi->vnr);
+ if (!peer_device)
+ return config_unknown_volume(connection, pi);
+ device = peer_device->device;
+
+ p_uuid = kmalloc(sizeof(u64)*UI_EXTENDED_SIZE, GFP_NOIO);
+ if (!p_uuid) {
+ drbd_err(device, "kmalloc of p_uuid failed\n");
+ return false;
+ }
+
+ for (i = UI_CURRENT; i < UI_EXTENDED_SIZE; i++)
+ p_uuid[i] = be64_to_cpu(p->uuid[i]);
+
+ kfree(device->p_uuid);
+ device->p_uuid = p_uuid;
+
+ if (device->state.conn < C_CONNECTED &&
+ device->state.disk < D_INCONSISTENT &&
+ device->state.role == R_PRIMARY &&
+ (device->ed_uuid & ~((u64)1)) != (p_uuid[UI_CURRENT] & ~((u64)1))) {
+ drbd_err(device, "Can only connect to data with current UUID=%016llX\n",
+ (unsigned long long)device->ed_uuid);
+ conn_request_state(peer_device->connection, NS(conn, C_DISCONNECTING), CS_HARD);
+ return -EIO;
+ }
+
+ if (get_ldev(device)) {
+ int skip_initial_sync =
+ device->state.conn == C_CONNECTED &&
+ peer_device->connection->agreed_pro_version >= 90 &&
+ device->ldev->md.uuid[UI_CURRENT] == UUID_JUST_CREATED &&
+ (p_uuid[UI_FLAGS] & 8);
+ if (skip_initial_sync) {
+ drbd_info(device, "Accepted new current UUID, preparing to skip initial sync\n");
+ drbd_bitmap_io(device, &drbd_bmio_clear_n_write,
+ "clear_n_write from receive_uuids",
+ BM_LOCKED_TEST_ALLOWED);
+ _drbd_uuid_set(device, UI_CURRENT, p_uuid[UI_CURRENT]);
+ _drbd_uuid_set(device, UI_BITMAP, 0);
+ _drbd_set_state(_NS2(device, disk, D_UP_TO_DATE, pdsk, D_UP_TO_DATE),
+ CS_VERBOSE, NULL);
+ drbd_md_sync(device);
+ updated_uuids = 1;
+ }
+ put_ldev(device);
+ } else if (device->state.disk < D_INCONSISTENT &&
+ device->state.role == R_PRIMARY) {
+ /* I am a diskless primary, the peer just created a new current UUID
+ for me. */
+ updated_uuids = drbd_set_ed_uuid(device, p_uuid[UI_CURRENT]);
+ }
+
+ /* Before we test for the disk state, we should wait until an eventually
+ ongoing cluster wide state change is finished. That is important if
+ we are primary and are detaching from our disk. We need to see the
+ new disk state... */
+ mutex_lock(device->state_mutex);
+ mutex_unlock(device->state_mutex);
+ if (device->state.conn >= C_CONNECTED && device->state.disk < D_INCONSISTENT)
+ updated_uuids |= drbd_set_ed_uuid(device, p_uuid[UI_CURRENT]);
+
+ if (updated_uuids)
+ drbd_print_uuids(device, "receiver updated UUIDs to");
+
+ return 0;
+}
+
+/**
+ * convert_state() - Converts the peer's view of the cluster state to our point of view
+ * @ps: The state as seen by the peer.
+ */
+static union drbd_state convert_state(union drbd_state ps)
+{
+ union drbd_state ms;
+
+ static enum drbd_conns c_tab[] = {
+ [C_WF_REPORT_PARAMS] = C_WF_REPORT_PARAMS,
+ [C_CONNECTED] = C_CONNECTED,
+
+ [C_STARTING_SYNC_S] = C_STARTING_SYNC_T,
+ [C_STARTING_SYNC_T] = C_STARTING_SYNC_S,
+ [C_DISCONNECTING] = C_TEAR_DOWN, /* C_NETWORK_FAILURE, */
+ [C_VERIFY_S] = C_VERIFY_T,
+ [C_MASK] = C_MASK,
+ };
+
+ ms.i = ps.i;
+
+ ms.conn = c_tab[ps.conn];
+ ms.peer = ps.role;
+ ms.role = ps.peer;
+ ms.pdsk = ps.disk;
+ ms.disk = ps.pdsk;
+ ms.peer_isp = (ps.aftr_isp | ps.user_isp);
+
+ return ms;
+}
+
+static int receive_req_state(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct drbd_peer_device *peer_device;
+ struct drbd_device *device;
+ struct p_req_state *p = pi->data;
+ union drbd_state mask, val;
+ enum drbd_state_rv rv;
+
+ peer_device = conn_peer_device(connection, pi->vnr);
+ if (!peer_device)
+ return -EIO;
+ device = peer_device->device;
+
+ mask.i = be32_to_cpu(p->mask);
+ val.i = be32_to_cpu(p->val);
+
+ if (test_bit(RESOLVE_CONFLICTS, &peer_device->connection->flags) &&
+ mutex_is_locked(device->state_mutex)) {
+ drbd_send_sr_reply(peer_device, SS_CONCURRENT_ST_CHG);
+ return 0;
+ }
+
+ mask = convert_state(mask);
+ val = convert_state(val);
+
+ rv = drbd_change_state(device, CS_VERBOSE, mask, val);
+ drbd_send_sr_reply(peer_device, rv);
+
+ drbd_md_sync(device);
+
+ return 0;
+}
+
+static int receive_req_conn_state(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct p_req_state *p = pi->data;
+ union drbd_state mask, val;
+ enum drbd_state_rv rv;
+
+ mask.i = be32_to_cpu(p->mask);
+ val.i = be32_to_cpu(p->val);
+
+ if (test_bit(RESOLVE_CONFLICTS, &connection->flags) &&
+ mutex_is_locked(&connection->cstate_mutex)) {
+ conn_send_sr_reply(connection, SS_CONCURRENT_ST_CHG);
+ return 0;
+ }
+
+ mask = convert_state(mask);
+ val = convert_state(val);
+
+ rv = conn_request_state(connection, mask, val, CS_VERBOSE | CS_LOCAL_ONLY | CS_IGN_OUTD_FAIL);
+ conn_send_sr_reply(connection, rv);
+
+ return 0;
+}
+
+static int receive_state(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct drbd_peer_device *peer_device;
+ struct drbd_device *device;
+ struct p_state *p = pi->data;
+ union drbd_state os, ns, peer_state;
+ enum drbd_disk_state real_peer_disk;
+ enum chg_state_flags cs_flags;
+ int rv;
+
+ peer_device = conn_peer_device(connection, pi->vnr);
+ if (!peer_device)
+ return config_unknown_volume(connection, pi);
+ device = peer_device->device;
+
+ peer_state.i = be32_to_cpu(p->state);
+
+ real_peer_disk = peer_state.disk;
+ if (peer_state.disk == D_NEGOTIATING) {
+ real_peer_disk = device->p_uuid[UI_FLAGS] & 4 ? D_INCONSISTENT : D_CONSISTENT;
+ drbd_info(device, "real peer disk state = %s\n", drbd_disk_str(real_peer_disk));
+ }
+
+ spin_lock_irq(&device->resource->req_lock);
+ retry:
+ os = ns = drbd_read_state(device);
+ spin_unlock_irq(&device->resource->req_lock);
+
+ /* If some other part of the code (asender thread, timeout)
+ * already decided to close the connection again,
+ * we must not "re-establish" it here. */
+ if (os.conn <= C_TEAR_DOWN)
+ return -ECONNRESET;
+
+ /* If this is the "end of sync" confirmation, usually the peer disk
+ * transitions from D_INCONSISTENT to D_UP_TO_DATE. For empty (0 bits
+ * set) resync started in PausedSyncT, or if the timing of pause-/
+ * unpause-sync events has been "just right", the peer disk may
+ * transition from D_CONSISTENT to D_UP_TO_DATE as well.
+ */
+ if ((os.pdsk == D_INCONSISTENT || os.pdsk == D_CONSISTENT) &&
+ real_peer_disk == D_UP_TO_DATE &&
+ os.conn > C_CONNECTED && os.disk == D_UP_TO_DATE) {
+ /* If we are (becoming) SyncSource, but peer is still in sync
+ * preparation, ignore its uptodate-ness to avoid flapping, it
+ * will change to inconsistent once the peer reaches active
+ * syncing states.
+ * It may have changed syncer-paused flags, however, so we
+ * cannot ignore this completely. */
+ if (peer_state.conn > C_CONNECTED &&
+ peer_state.conn < C_SYNC_SOURCE)
+ real_peer_disk = D_INCONSISTENT;
+
+ /* if peer_state changes to connected at the same time,
+ * it explicitly notifies us that it finished resync.
+ * Maybe we should finish it up, too? */
+ else if (os.conn >= C_SYNC_SOURCE &&
+ peer_state.conn == C_CONNECTED) {
+ if (drbd_bm_total_weight(device) <= device->rs_failed)
+ drbd_resync_finished(device);
+ return 0;
+ }
+ }
+
+ /* explicit verify finished notification, stop sector reached. */
+ if (os.conn == C_VERIFY_T && os.disk == D_UP_TO_DATE &&
+ peer_state.conn == C_CONNECTED && real_peer_disk == D_UP_TO_DATE) {
+ ov_out_of_sync_print(device);
+ drbd_resync_finished(device);
+ return 0;
+ }
+
+ /* peer says his disk is inconsistent, while we think it is uptodate,
+ * and this happens while the peer still thinks we have a sync going on,
+ * but we think we are already done with the sync.
+ * We ignore this to avoid flapping pdsk.
+ * This should not happen, if the peer is a recent version of drbd. */
+ if (os.pdsk == D_UP_TO_DATE && real_peer_disk == D_INCONSISTENT &&
+ os.conn == C_CONNECTED && peer_state.conn > C_SYNC_SOURCE)
+ real_peer_disk = D_UP_TO_DATE;
+
+ if (ns.conn == C_WF_REPORT_PARAMS)
+ ns.conn = C_CONNECTED;
+
+ if (peer_state.conn == C_AHEAD)
+ ns.conn = C_BEHIND;
+
+ if (device->p_uuid && peer_state.disk >= D_NEGOTIATING &&
+ get_ldev_if_state(device, D_NEGOTIATING)) {
+ int cr; /* consider resync */
+
+ /* if we established a new connection */
+ cr = (os.conn < C_CONNECTED);
+ /* if we had an established connection
+ * and one of the nodes newly attaches a disk */
+ cr |= (os.conn == C_CONNECTED &&
+ (peer_state.disk == D_NEGOTIATING ||
+ os.disk == D_NEGOTIATING));
+ /* if we have both been inconsistent, and the peer has been
+ * forced to be UpToDate with --overwrite-data */
+ cr |= test_bit(CONSIDER_RESYNC, &device->flags);
+ /* if we had been plain connected, and the admin requested to
+ * start a sync by "invalidate" or "invalidate-remote" */
+ cr |= (os.conn == C_CONNECTED &&
+ (peer_state.conn >= C_STARTING_SYNC_S &&
+ peer_state.conn <= C_WF_BITMAP_T));
+
+ if (cr)
+ ns.conn = drbd_sync_handshake(peer_device, peer_state.role, real_peer_disk);
+
+ put_ldev(device);
+ if (ns.conn == C_MASK) {
+ ns.conn = C_CONNECTED;
+ if (device->state.disk == D_NEGOTIATING) {
+ drbd_force_state(device, NS(disk, D_FAILED));
+ } else if (peer_state.disk == D_NEGOTIATING) {
+ drbd_err(device, "Disk attach process on the peer node was aborted.\n");
+ peer_state.disk = D_DISKLESS;
+ real_peer_disk = D_DISKLESS;
+ } else {
+ if (test_and_clear_bit(CONN_DRY_RUN, &peer_device->connection->flags))
+ return -EIO;
+ D_ASSERT(device, os.conn == C_WF_REPORT_PARAMS);
+ conn_request_state(peer_device->connection, NS(conn, C_DISCONNECTING), CS_HARD);
+ return -EIO;
+ }
+ }
+ }
+
+ spin_lock_irq(&device->resource->req_lock);
+ if (os.i != drbd_read_state(device).i)
+ goto retry;
+ clear_bit(CONSIDER_RESYNC, &device->flags);
+ ns.peer = peer_state.role;
+ ns.pdsk = real_peer_disk;
+ ns.peer_isp = (peer_state.aftr_isp | peer_state.user_isp);
+ if ((ns.conn == C_CONNECTED || ns.conn == C_WF_BITMAP_S) && ns.disk == D_NEGOTIATING)
+ ns.disk = device->new_state_tmp.disk;
+ cs_flags = CS_VERBOSE + (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED ? 0 : CS_HARD);
+ if (ns.pdsk == D_CONSISTENT && drbd_suspended(device) && ns.conn == C_CONNECTED && os.conn < C_CONNECTED &&
+ test_bit(NEW_CUR_UUID, &device->flags)) {
+ /* Do not allow tl_restart(RESEND) for a rebooted peer. We can only allow this
+ for temporal network outages! */
+ spin_unlock_irq(&device->resource->req_lock);
+ drbd_err(device, "Aborting Connect, can not thaw IO with an only Consistent peer\n");
+ tl_clear(peer_device->connection);
+ drbd_uuid_new_current(device);
+ clear_bit(NEW_CUR_UUID, &device->flags);
+ conn_request_state(peer_device->connection, NS2(conn, C_PROTOCOL_ERROR, susp, 0), CS_HARD);
+ return -EIO;
+ }
+ rv = _drbd_set_state(device, ns, cs_flags, NULL);
+ ns = drbd_read_state(device);
+ spin_unlock_irq(&device->resource->req_lock);
+
+ if (rv < SS_SUCCESS) {
+ conn_request_state(peer_device->connection, NS(conn, C_DISCONNECTING), CS_HARD);
+ return -EIO;
+ }
+
+ if (os.conn > C_WF_REPORT_PARAMS) {
+ if (ns.conn > C_CONNECTED && peer_state.conn <= C_CONNECTED &&
+ peer_state.disk != D_NEGOTIATING ) {
+ /* we want resync, peer has not yet decided to sync... */
+ /* Nowadays only used when forcing a node into primary role and
+ setting its disk to UpToDate with that */
+ drbd_send_uuids(peer_device);
+ drbd_send_current_state(peer_device);
+ }
+ }
+
+ clear_bit(DISCARD_MY_DATA, &device->flags);
+
+ drbd_md_sync(device); /* update connected indicator, la_size_sect, ... */
+
+ return 0;
+}
+
+static int receive_sync_uuid(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct drbd_peer_device *peer_device;
+ struct drbd_device *device;
+ struct p_rs_uuid *p = pi->data;
+
+ peer_device = conn_peer_device(connection, pi->vnr);
+ if (!peer_device)
+ return -EIO;
+ device = peer_device->device;
+
+ wait_event(device->misc_wait,
+ device->state.conn == C_WF_SYNC_UUID ||
+ device->state.conn == C_BEHIND ||
+ device->state.conn < C_CONNECTED ||
+ device->state.disk < D_NEGOTIATING);
+
+ /* D_ASSERT(device, device->state.conn == C_WF_SYNC_UUID ); */
+
+ /* Here the _drbd_uuid_ functions are right, current should
+ _not_ be rotated into the history */
+ if (get_ldev_if_state(device, D_NEGOTIATING)) {
+ _drbd_uuid_set(device, UI_CURRENT, be64_to_cpu(p->uuid));
+ _drbd_uuid_set(device, UI_BITMAP, 0UL);
+
+ drbd_print_uuids(device, "updated sync uuid");
+ drbd_start_resync(device, C_SYNC_TARGET);
+
+ put_ldev(device);
+ } else
+ drbd_err(device, "Ignoring SyncUUID packet!\n");
+
+ return 0;
+}
+
+/**
+ * receive_bitmap_plain
+ *
+ * Return 0 when done, 1 when another iteration is needed, and a negative error
+ * code upon failure.
+ */
+static int
+receive_bitmap_plain(struct drbd_peer_device *peer_device, unsigned int size,
+ unsigned long *p, struct bm_xfer_ctx *c)
+{
+ unsigned int data_size = DRBD_SOCKET_BUFFER_SIZE -
+ drbd_header_size(peer_device->connection);
+ unsigned int num_words = min_t(size_t, data_size / sizeof(*p),
+ c->bm_words - c->word_offset);
+ unsigned int want = num_words * sizeof(*p);
+ int err;
+
+ if (want != size) {
+ drbd_err(peer_device, "%s:want (%u) != size (%u)\n", __func__, want, size);
+ return -EIO;
+ }
+ if (want == 0)
+ return 0;
+ err = drbd_recv_all(peer_device->connection, p, want);
+ if (err)
+ return err;
+
+ drbd_bm_merge_lel(peer_device->device, c->word_offset, num_words, p);
+
+ c->word_offset += num_words;
+ c->bit_offset = c->word_offset * BITS_PER_LONG;
+ if (c->bit_offset > c->bm_bits)
+ c->bit_offset = c->bm_bits;
+
+ return 1;
+}
+
+static enum drbd_bitmap_code dcbp_get_code(struct p_compressed_bm *p)
+{
+ return (enum drbd_bitmap_code)(p->encoding & 0x0f);
+}
+
+static int dcbp_get_start(struct p_compressed_bm *p)
+{
+ return (p->encoding & 0x80) != 0;
+}
+
+static int dcbp_get_pad_bits(struct p_compressed_bm *p)
+{
+ return (p->encoding >> 4) & 0x7;
+}
+
+/**
+ * recv_bm_rle_bits
+ *
+ * Return 0 when done, 1 when another iteration is needed, and a negative error
+ * code upon failure.
+ */
+static int
+recv_bm_rle_bits(struct drbd_peer_device *peer_device,
+ struct p_compressed_bm *p,
+ struct bm_xfer_ctx *c,
+ unsigned int len)
+{
+ struct bitstream bs;
+ u64 look_ahead;
+ u64 rl;
+ u64 tmp;
+ unsigned long s = c->bit_offset;
+ unsigned long e;
+ int toggle = dcbp_get_start(p);
+ int have;
+ int bits;
+
+ bitstream_init(&bs, p->code, len, dcbp_get_pad_bits(p));
+
+ bits = bitstream_get_bits(&bs, &look_ahead, 64);
+ if (bits < 0)
+ return -EIO;
+
+ for (have = bits; have > 0; s += rl, toggle = !toggle) {
+ bits = vli_decode_bits(&rl, look_ahead);
+ if (bits <= 0)
+ return -EIO;
+
+ if (toggle) {
+ e = s + rl -1;
+ if (e >= c->bm_bits) {
+ drbd_err(peer_device, "bitmap overflow (e:%lu) while decoding bm RLE packet\n", e);
+ return -EIO;
+ }
+ _drbd_bm_set_bits(peer_device->device, s, e);
+ }
+
+ if (have < bits) {
+ drbd_err(peer_device, "bitmap decoding error: h:%d b:%d la:0x%08llx l:%u/%u\n",
+ have, bits, look_ahead,
+ (unsigned int)(bs.cur.b - p->code),
+ (unsigned int)bs.buf_len);
+ return -EIO;
+ }
+ /* if we consumed all 64 bits, assign 0; >> 64 is "undefined"; */
+ if (likely(bits < 64))
+ look_ahead >>= bits;
+ else
+ look_ahead = 0;
+ have -= bits;
+
+ bits = bitstream_get_bits(&bs, &tmp, 64 - have);
+ if (bits < 0)
+ return -EIO;
+ look_ahead |= tmp << have;
+ have += bits;
+ }
+
+ c->bit_offset = s;
+ bm_xfer_ctx_bit_to_word_offset(c);
+
+ return (s != c->bm_bits);
+}
+
+/**
+ * decode_bitmap_c
+ *
+ * Return 0 when done, 1 when another iteration is needed, and a negative error
+ * code upon failure.
+ */
+static int
+decode_bitmap_c(struct drbd_peer_device *peer_device,
+ struct p_compressed_bm *p,
+ struct bm_xfer_ctx *c,
+ unsigned int len)
+{
+ if (dcbp_get_code(p) == RLE_VLI_Bits)
+ return recv_bm_rle_bits(peer_device, p, c, len - sizeof(*p));
+
+ /* other variants had been implemented for evaluation,
+ * but have been dropped as this one turned out to be "best"
+ * during all our tests. */
+
+ drbd_err(peer_device, "receive_bitmap_c: unknown encoding %u\n", p->encoding);
+ conn_request_state(peer_device->connection, NS(conn, C_PROTOCOL_ERROR), CS_HARD);
+ return -EIO;
+}
+
+void INFO_bm_xfer_stats(struct drbd_device *device,
+ const char *direction, struct bm_xfer_ctx *c)
+{
+ /* what would it take to transfer it "plaintext" */
+ unsigned int header_size = drbd_header_size(first_peer_device(device)->connection);
+ unsigned int data_size = DRBD_SOCKET_BUFFER_SIZE - header_size;
+ unsigned int plain =
+ header_size * (DIV_ROUND_UP(c->bm_words, data_size) + 1) +
+ c->bm_words * sizeof(unsigned long);
+ unsigned int total = c->bytes[0] + c->bytes[1];
+ unsigned int r;
+
+ /* total can not be zero. but just in case: */
+ if (total == 0)
+ return;
+
+ /* don't report if not compressed */
+ if (total >= plain)
+ return;
+
+ /* total < plain. check for overflow, still */
+ r = (total > UINT_MAX/1000) ? (total / (plain/1000))
+ : (1000 * total / plain);
+
+ if (r > 1000)
+ r = 1000;
+
+ r = 1000 - r;
+ drbd_info(device, "%s bitmap stats [Bytes(packets)]: plain %u(%u), RLE %u(%u), "
+ "total %u; compression: %u.%u%%\n",
+ direction,
+ c->bytes[1], c->packets[1],
+ c->bytes[0], c->packets[0],
+ total, r/10, r % 10);
+}
+
+/* Since we are processing the bitfield from lower addresses to higher,
+ it does not matter if the process it in 32 bit chunks or 64 bit
+ chunks as long as it is little endian. (Understand it as byte stream,
+ beginning with the lowest byte...) If we would use big endian
+ we would need to process it from the highest address to the lowest,
+ in order to be agnostic to the 32 vs 64 bits issue.
+
+ returns 0 on failure, 1 if we successfully received it. */
+static int receive_bitmap(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct drbd_peer_device *peer_device;
+ struct drbd_device *device;
+ struct bm_xfer_ctx c;
+ int err;
+
+ peer_device = conn_peer_device(connection, pi->vnr);
+ if (!peer_device)
+ return -EIO;
+ device = peer_device->device;
+
+ drbd_bm_lock(device, "receive bitmap", BM_LOCKED_SET_ALLOWED);
+ /* you are supposed to send additional out-of-sync information
+ * if you actually set bits during this phase */
+
+ c = (struct bm_xfer_ctx) {
+ .bm_bits = drbd_bm_bits(device),
+ .bm_words = drbd_bm_words(device),
+ };
+
+ for(;;) {
+ if (pi->cmd == P_BITMAP)
+ err = receive_bitmap_plain(peer_device, pi->size, pi->data, &c);
+ else if (pi->cmd == P_COMPRESSED_BITMAP) {
+ /* MAYBE: sanity check that we speak proto >= 90,
+ * and the feature is enabled! */
+ struct p_compressed_bm *p = pi->data;
+
+ if (pi->size > DRBD_SOCKET_BUFFER_SIZE - drbd_header_size(connection)) {
+ drbd_err(device, "ReportCBitmap packet too large\n");
+ err = -EIO;
+ goto out;
+ }
+ if (pi->size <= sizeof(*p)) {
+ drbd_err(device, "ReportCBitmap packet too small (l:%u)\n", pi->size);
+ err = -EIO;
+ goto out;
+ }
+ err = drbd_recv_all(peer_device->connection, p, pi->size);
+ if (err)
+ goto out;
+ err = decode_bitmap_c(peer_device, p, &c, pi->size);
+ } else {
+ drbd_warn(device, "receive_bitmap: cmd neither ReportBitMap nor ReportCBitMap (is 0x%x)", pi->cmd);
+ err = -EIO;
+ goto out;
+ }
+
+ c.packets[pi->cmd == P_BITMAP]++;
+ c.bytes[pi->cmd == P_BITMAP] += drbd_header_size(connection) + pi->size;
+
+ if (err <= 0) {
+ if (err < 0)
+ goto out;
+ break;
+ }
+ err = drbd_recv_header(peer_device->connection, pi);
+ if (err)
+ goto out;
+ }
+
+ INFO_bm_xfer_stats(device, "receive", &c);
+
+ if (device->state.conn == C_WF_BITMAP_T) {
+ enum drbd_state_rv rv;
+
+ err = drbd_send_bitmap(device);
+ if (err)
+ goto out;
+ /* Omit CS_ORDERED with this state transition to avoid deadlocks. */
+ rv = _drbd_request_state(device, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE);
+ D_ASSERT(device, rv == SS_SUCCESS);
+ } else if (device->state.conn != C_WF_BITMAP_S) {
+ /* admin may have requested C_DISCONNECTING,
+ * other threads may have noticed network errors */
+ drbd_info(device, "unexpected cstate (%s) in receive_bitmap\n",
+ drbd_conn_str(device->state.conn));
+ }
+ err = 0;
+
+ out:
+ drbd_bm_unlock(device);
+ if (!err && device->state.conn == C_WF_BITMAP_S)
+ drbd_start_resync(device, C_SYNC_SOURCE);
+ return err;
+}
+
+static int receive_skip(struct drbd_connection *connection, struct packet_info *pi)
+{
+ drbd_warn(connection, "skipping unknown optional packet type %d, l: %d!\n",
+ pi->cmd, pi->size);
+
+ return ignore_remaining_packet(connection, pi);
+}
+
+static int receive_UnplugRemote(struct drbd_connection *connection, struct packet_info *pi)
+{
+ /* Make sure we've acked all the TCP data associated
+ * with the data requests being unplugged */
+ drbd_tcp_quickack(connection->data.socket);
+
+ return 0;
+}
+
+static int receive_out_of_sync(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct drbd_peer_device *peer_device;
+ struct drbd_device *device;
+ struct p_block_desc *p = pi->data;
+
+ peer_device = conn_peer_device(connection, pi->vnr);
+ if (!peer_device)
+ return -EIO;
+ device = peer_device->device;
+
+ switch (device->state.conn) {
+ case C_WF_SYNC_UUID:
+ case C_WF_BITMAP_T:
+ case C_BEHIND:
+ break;
+ default:
+ drbd_err(device, "ASSERT FAILED cstate = %s, expected: WFSyncUUID|WFBitMapT|Behind\n",
+ drbd_conn_str(device->state.conn));
+ }
+
+ drbd_set_out_of_sync(device, be64_to_cpu(p->sector), be32_to_cpu(p->blksize));
+
+ return 0;
+}
+
+struct data_cmd {
+ int expect_payload;
+ size_t pkt_size;
+ int (*fn)(struct drbd_connection *, struct packet_info *);
+};
+
+static struct data_cmd drbd_cmd_handler[] = {
+ [P_DATA] = { 1, sizeof(struct p_data), receive_Data },
+ [P_DATA_REPLY] = { 1, sizeof(struct p_data), receive_DataReply },
+ [P_RS_DATA_REPLY] = { 1, sizeof(struct p_data), receive_RSDataReply } ,
+ [P_BARRIER] = { 0, sizeof(struct p_barrier), receive_Barrier } ,
+ [P_BITMAP] = { 1, 0, receive_bitmap } ,
+ [P_COMPRESSED_BITMAP] = { 1, 0, receive_bitmap } ,
+ [P_UNPLUG_REMOTE] = { 0, 0, receive_UnplugRemote },
+ [P_DATA_REQUEST] = { 0, sizeof(struct p_block_req), receive_DataRequest },
+ [P_RS_DATA_REQUEST] = { 0, sizeof(struct p_block_req), receive_DataRequest },
+ [P_SYNC_PARAM] = { 1, 0, receive_SyncParam },
+ [P_SYNC_PARAM89] = { 1, 0, receive_SyncParam },
+ [P_PROTOCOL] = { 1, sizeof(struct p_protocol), receive_protocol },
+ [P_UUIDS] = { 0, sizeof(struct p_uuids), receive_uuids },
+ [P_SIZES] = { 0, sizeof(struct p_sizes), receive_sizes },
+ [P_STATE] = { 0, sizeof(struct p_state), receive_state },
+ [P_STATE_CHG_REQ] = { 0, sizeof(struct p_req_state), receive_req_state },
+ [P_SYNC_UUID] = { 0, sizeof(struct p_rs_uuid), receive_sync_uuid },
+ [P_OV_REQUEST] = { 0, sizeof(struct p_block_req), receive_DataRequest },
+ [P_OV_REPLY] = { 1, sizeof(struct p_block_req), receive_DataRequest },
+ [P_CSUM_RS_REQUEST] = { 1, sizeof(struct p_block_req), receive_DataRequest },
+ [P_DELAY_PROBE] = { 0, sizeof(struct p_delay_probe93), receive_skip },
+ [P_OUT_OF_SYNC] = { 0, sizeof(struct p_block_desc), receive_out_of_sync },
+ [P_CONN_ST_CHG_REQ] = { 0, sizeof(struct p_req_state), receive_req_conn_state },
+ [P_PROTOCOL_UPDATE] = { 1, sizeof(struct p_protocol), receive_protocol },
+ [P_TRIM] = { 0, sizeof(struct p_trim), receive_Data },
+};
+
+static void drbdd(struct drbd_connection *connection)
+{
+ struct packet_info pi;
+ size_t shs; /* sub header size */
+ int err;
+
+ while (get_t_state(&connection->receiver) == RUNNING) {
+ struct data_cmd *cmd;
+
+ drbd_thread_current_set_cpu(&connection->receiver);
+ update_receiver_timing_details(connection, drbd_recv_header);
+ if (drbd_recv_header(connection, &pi))
+ goto err_out;
+
+ cmd = &drbd_cmd_handler[pi.cmd];
+ if (unlikely(pi.cmd >= ARRAY_SIZE(drbd_cmd_handler) || !cmd->fn)) {
+ drbd_err(connection, "Unexpected data packet %s (0x%04x)",
+ cmdname(pi.cmd), pi.cmd);
+ goto err_out;
+ }
+
+ shs = cmd->pkt_size;
+ if (pi.size > shs && !cmd->expect_payload) {
+ drbd_err(connection, "No payload expected %s l:%d\n",
+ cmdname(pi.cmd), pi.size);
+ goto err_out;
+ }
+
+ if (shs) {
+ update_receiver_timing_details(connection, drbd_recv_all_warn);
+ err = drbd_recv_all_warn(connection, pi.data, shs);
+ if (err)
+ goto err_out;
+ pi.size -= shs;
+ }
+
+ update_receiver_timing_details(connection, cmd->fn);
+ err = cmd->fn(connection, &pi);
+ if (err) {
+ drbd_err(connection, "error receiving %s, e: %d l: %d!\n",
+ cmdname(pi.cmd), err, pi.size);
+ goto err_out;
+ }
+ }
+ return;
+
+ err_out:
+ conn_request_state(connection, NS(conn, C_PROTOCOL_ERROR), CS_HARD);
+}
+
+static void conn_disconnect(struct drbd_connection *connection)
+{
+ struct drbd_peer_device *peer_device;
+ enum drbd_conns oc;
+ int vnr;
+
+ if (connection->cstate == C_STANDALONE)
+ return;
+
+ /* We are about to start the cleanup after connection loss.
+ * Make sure drbd_make_request knows about that.
+ * Usually we should be in some network failure state already,
+ * but just in case we are not, we fix it up here.
+ */
+ conn_request_state(connection, NS(conn, C_NETWORK_FAILURE), CS_HARD);
+
+ /* asender does not clean up anything. it must not interfere, either */
+ drbd_thread_stop(&connection->asender);
+ drbd_free_sock(connection);
+
+ 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_disconnected(peer_device);
+ kref_put(&device->kref, drbd_destroy_device);
+ rcu_read_lock();
+ }
+ rcu_read_unlock();
+
+ if (!list_empty(&connection->current_epoch->list))
+ drbd_err(connection, "ASSERTION FAILED: connection->current_epoch->list not empty\n");
+ /* ok, no more ee's on the fly, it is safe to reset the epoch_size */
+ atomic_set(&connection->current_epoch->epoch_size, 0);
+ connection->send.seen_any_write_yet = false;
+
+ drbd_info(connection, "Connection closed\n");
+
+ if (conn_highest_role(connection) == R_PRIMARY && conn_highest_pdsk(connection) >= D_UNKNOWN)
+ conn_try_outdate_peer_async(connection);
+
+ spin_lock_irq(&connection->resource->req_lock);
+ oc = connection->cstate;
+ if (oc >= C_UNCONNECTED)
+ _conn_request_state(connection, NS(conn, C_UNCONNECTED), CS_VERBOSE);
+
+ spin_unlock_irq(&connection->resource->req_lock);
+
+ if (oc == C_DISCONNECTING)
+ conn_request_state(connection, NS(conn, C_STANDALONE), CS_VERBOSE | CS_HARD);
+}
+
+static int drbd_disconnected(struct drbd_peer_device *peer_device)
+{
+ struct drbd_device *device = peer_device->device;
+ unsigned int i;
+
+ /* wait for current activity to cease. */
+ spin_lock_irq(&device->resource->req_lock);
+ _drbd_wait_ee_list_empty(device, &device->active_ee);
+ _drbd_wait_ee_list_empty(device, &device->sync_ee);
+ _drbd_wait_ee_list_empty(device, &device->read_ee);
+ spin_unlock_irq(&device->resource->req_lock);
+
+ /* We do not have data structures that would allow us to
+ * get the rs_pending_cnt down to 0 again.
+ * * On C_SYNC_TARGET we do not have any data structures describing
+ * the pending RSDataRequest's we have sent.
+ * * On C_SYNC_SOURCE there is no data structure that tracks
+ * the P_RS_DATA_REPLY blocks that we sent to the SyncTarget.
+ * And no, it is not the sum of the reference counts in the
+ * resync_LRU. The resync_LRU tracks the whole operation including
+ * the disk-IO, while the rs_pending_cnt only tracks the blocks
+ * on the fly. */
+ drbd_rs_cancel_all(device);
+ device->rs_total = 0;
+ device->rs_failed = 0;
+ atomic_set(&device->rs_pending_cnt, 0);
+ wake_up(&device->misc_wait);
+
+ del_timer_sync(&device->resync_timer);
+ resync_timer_fn((unsigned long)device);
+
+ /* wait for all w_e_end_data_req, w_e_end_rsdata_req, w_send_barrier,
+ * w_make_resync_request etc. which may still be on the worker queue
+ * to be "canceled" */
+ drbd_flush_workqueue(&peer_device->connection->sender_work);
+
+ drbd_finish_peer_reqs(device);
+
+ /* This second workqueue flush is necessary, since drbd_finish_peer_reqs()
+ might have issued a work again. The one before drbd_finish_peer_reqs() is
+ necessary to reclain net_ee in drbd_finish_peer_reqs(). */
+ drbd_flush_workqueue(&peer_device->connection->sender_work);
+
+ /* need to do it again, drbd_finish_peer_reqs() may have populated it
+ * again via drbd_try_clear_on_disk_bm(). */
+ drbd_rs_cancel_all(device);
+
+ kfree(device->p_uuid);
+ device->p_uuid = NULL;
+
+ if (!drbd_suspended(device))
+ tl_clear(peer_device->connection);
+
+ drbd_md_sync(device);
+
+ /* serialize with bitmap writeout triggered by the state change,
+ * if any. */
+ wait_event(device->misc_wait, !test_bit(BITMAP_IO, &device->flags));
+
+ /* tcp_close and release of sendpage pages can be deferred. I don't
+ * want to use SO_LINGER, because apparently it can be deferred for
+ * more than 20 seconds (longest time I checked).
+ *
+ * Actually we don't care for exactly when the network stack does its
+ * put_page(), but release our reference on these pages right here.
+ */
+ i = drbd_free_peer_reqs(device, &device->net_ee);
+ if (i)
+ drbd_info(device, "net_ee not empty, killed %u entries\n", i);
+ i = atomic_read(&device->pp_in_use_by_net);
+ if (i)
+ drbd_info(device, "pp_in_use_by_net = %d, expected 0\n", i);
+ i = atomic_read(&device->pp_in_use);
+ if (i)
+ drbd_info(device, "pp_in_use = %d, expected 0\n", i);
+
+ D_ASSERT(device, list_empty(&device->read_ee));
+ D_ASSERT(device, list_empty(&device->active_ee));
+ D_ASSERT(device, list_empty(&device->sync_ee));
+ D_ASSERT(device, list_empty(&device->done_ee));
+
+ return 0;
+}
+
+/*
+ * We support PRO_VERSION_MIN to PRO_VERSION_MAX. The protocol version
+ * we can agree on is stored in agreed_pro_version.
+ *
+ * feature flags and the reserved array should be enough room for future
+ * enhancements of the handshake protocol, and possible plugins...
+ *
+ * for now, they are expected to be zero, but ignored.
+ */
+static int drbd_send_features(struct drbd_connection *connection)
+{
+ struct drbd_socket *sock;
+ struct p_connection_features *p;
+
+ sock = &connection->data;
+ p = conn_prepare_command(connection, sock);
+ if (!p)
+ return -EIO;
+ memset(p, 0, sizeof(*p));
+ p->protocol_min = cpu_to_be32(PRO_VERSION_MIN);
+ p->protocol_max = cpu_to_be32(PRO_VERSION_MAX);
+ p->feature_flags = cpu_to_be32(PRO_FEATURES);
+ return conn_send_command(connection, sock, P_CONNECTION_FEATURES, sizeof(*p), NULL, 0);
+}
+
+/*
+ * 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.
+ */
+static int drbd_do_features(struct drbd_connection *connection)
+{
+ /* ASSERT current == connection->receiver ... */
+ struct p_connection_features *p;
+ const int expect = sizeof(struct p_connection_features);
+ struct packet_info pi;
+ int err;
+
+ err = drbd_send_features(connection);
+ if (err)
+ return 0;
+
+ err = drbd_recv_header(connection, &pi);
+ if (err)
+ return 0;
+
+ if (pi.cmd != P_CONNECTION_FEATURES) {
+ drbd_err(connection, "expected ConnectionFeatures packet, received: %s (0x%04x)\n",
+ cmdname(pi.cmd), pi.cmd);
+ return -1;
+ }
+
+ if (pi.size != expect) {
+ drbd_err(connection, "expected ConnectionFeatures length: %u, received: %u\n",
+ expect, pi.size);
+ return -1;
+ }
+
+ p = pi.data;
+ err = drbd_recv_all_warn(connection, p, expect);
+ if (err)
+ return 0;
+
+ p->protocol_min = be32_to_cpu(p->protocol_min);
+ p->protocol_max = be32_to_cpu(p->protocol_max);
+ if (p->protocol_max == 0)
+ p->protocol_max = p->protocol_min;
+
+ if (PRO_VERSION_MAX < p->protocol_min ||
+ PRO_VERSION_MIN > p->protocol_max)
+ goto incompat;
+
+ connection->agreed_pro_version = min_t(int, PRO_VERSION_MAX, p->protocol_max);
+ connection->agreed_features = PRO_FEATURES & be32_to_cpu(p->feature_flags);
+
+ drbd_info(connection, "Handshake successful: "
+ "Agreed network protocol version %d\n", connection->agreed_pro_version);
+
+ drbd_info(connection, "Agreed to%ssupport TRIM on protocol level\n",
+ connection->agreed_features & FF_TRIM ? " " : " not ");
+
+ return 1;
+
+ incompat:
+ drbd_err(connection, "incompatible DRBD dialects: "
+ "I support %d-%d, peer supports %d-%d\n",
+ PRO_VERSION_MIN, PRO_VERSION_MAX,
+ p->protocol_min, p->protocol_max);
+ return -1;
+}
+
+#if !defined(CONFIG_CRYPTO_HMAC) && !defined(CONFIG_CRYPTO_HMAC_MODULE)
+static int drbd_do_auth(struct drbd_connection *connection)
+{
+ drbd_err(connection, "This kernel was build without CONFIG_CRYPTO_HMAC.\n");
+ drbd_err(connection, "You need to disable 'cram-hmac-alg' in drbd.conf.\n");
+ return -1;
+}
+#else
+#define CHALLENGE_LEN 64
+
+/* Return value:
+ 1 - auth succeeded,
+ 0 - failed, try again (network error),
+ -1 - auth failed, don't try again.
+*/
+
+static int drbd_do_auth(struct drbd_connection *connection)
+{
+ struct drbd_socket *sock;
+ char my_challenge[CHALLENGE_LEN]; /* 64 Bytes... */
+ struct scatterlist sg;
+ char *response = NULL;
+ char *right_response = NULL;
+ char *peers_ch = NULL;
+ unsigned int key_len;
+ char secret[SHARED_SECRET_MAX]; /* 64 byte */
+ unsigned int resp_size;
+ struct hash_desc desc;
+ struct packet_info pi;
+ struct net_conf *nc;
+ int err, rv;
+
+ /* FIXME: Put the challenge/response into the preallocated socket buffer. */
+
+ rcu_read_lock();
+ nc = rcu_dereference(connection->net_conf);
+ key_len = strlen(nc->shared_secret);
+ memcpy(secret, nc->shared_secret, key_len);
+ rcu_read_unlock();
+
+ desc.tfm = connection->cram_hmac_tfm;
+ desc.flags = 0;
+
+ rv = crypto_hash_setkey(connection->cram_hmac_tfm, (u8 *)secret, key_len);
+ if (rv) {
+ drbd_err(connection, "crypto_hash_setkey() failed with %d\n", rv);
+ rv = -1;
+ goto fail;
+ }
+
+ get_random_bytes(my_challenge, CHALLENGE_LEN);
+
+ sock = &connection->data;
+ if (!conn_prepare_command(connection, sock)) {
+ rv = 0;
+ goto fail;
+ }
+ rv = !conn_send_command(connection, sock, P_AUTH_CHALLENGE, 0,
+ my_challenge, CHALLENGE_LEN);
+ if (!rv)
+ goto fail;
+
+ err = drbd_recv_header(connection, &pi);
+ if (err) {
+ rv = 0;
+ goto fail;
+ }
+
+ if (pi.cmd != P_AUTH_CHALLENGE) {
+ drbd_err(connection, "expected AuthChallenge packet, received: %s (0x%04x)\n",
+ cmdname(pi.cmd), pi.cmd);
+ rv = 0;
+ goto fail;
+ }
+
+ if (pi.size > CHALLENGE_LEN * 2) {
+ drbd_err(connection, "expected AuthChallenge payload too big.\n");
+ rv = -1;
+ goto fail;
+ }
+
+ if (pi.size < CHALLENGE_LEN) {
+ drbd_err(connection, "AuthChallenge payload too small.\n");
+ rv = -1;
+ goto fail;
+ }
+
+ peers_ch = kmalloc(pi.size, GFP_NOIO);
+ if (peers_ch == NULL) {
+ drbd_err(connection, "kmalloc of peers_ch failed\n");
+ rv = -1;
+ goto fail;
+ }
+
+ err = drbd_recv_all_warn(connection, peers_ch, pi.size);
+ if (err) {
+ rv = 0;
+ goto fail;
+ }
+
+ if (!memcmp(my_challenge, peers_ch, CHALLENGE_LEN)) {
+ drbd_err(connection, "Peer presented the same challenge!\n");
+ rv = -1;
+ goto fail;
+ }
+
+ resp_size = crypto_hash_digestsize(connection->cram_hmac_tfm);
+ response = kmalloc(resp_size, GFP_NOIO);
+ if (response == NULL) {
+ drbd_err(connection, "kmalloc of response failed\n");
+ rv = -1;
+ goto fail;
+ }
+
+ sg_init_table(&sg, 1);
+ sg_set_buf(&sg, peers_ch, pi.size);
+
+ rv = crypto_hash_digest(&desc, &sg, sg.length, response);
+ if (rv) {
+ drbd_err(connection, "crypto_hash_digest() failed with %d\n", rv);
+ rv = -1;
+ goto fail;
+ }
+
+ if (!conn_prepare_command(connection, sock)) {
+ rv = 0;
+ goto fail;
+ }
+ rv = !conn_send_command(connection, sock, P_AUTH_RESPONSE, 0,
+ response, resp_size);
+ if (!rv)
+ goto fail;
+
+ err = drbd_recv_header(connection, &pi);
+ if (err) {
+ rv = 0;
+ goto fail;
+ }
+
+ if (pi.cmd != P_AUTH_RESPONSE) {
+ drbd_err(connection, "expected AuthResponse packet, received: %s (0x%04x)\n",
+ cmdname(pi.cmd), pi.cmd);
+ rv = 0;
+ goto fail;
+ }
+
+ if (pi.size != resp_size) {
+ drbd_err(connection, "expected AuthResponse payload of wrong size\n");
+ rv = 0;
+ goto fail;
+ }
+
+ err = drbd_recv_all_warn(connection, response , resp_size);
+ if (err) {
+ rv = 0;
+ goto fail;
+ }
+
+ right_response = kmalloc(resp_size, GFP_NOIO);
+ if (right_response == NULL) {
+ drbd_err(connection, "kmalloc of right_response failed\n");
+ rv = -1;
+ goto fail;
+ }
+
+ sg_set_buf(&sg, my_challenge, CHALLENGE_LEN);
+
+ rv = crypto_hash_digest(&desc, &sg, sg.length, right_response);
+ if (rv) {
+ drbd_err(connection, "crypto_hash_digest() failed with %d\n", rv);
+ rv = -1;
+ goto fail;
+ }
+
+ rv = !memcmp(response, right_response, resp_size);
+
+ if (rv)
+ drbd_info(connection, "Peer authenticated using %d bytes HMAC\n",
+ resp_size);
+ else
+ rv = -1;
+
+ fail:
+ kfree(peers_ch);
+ kfree(response);
+ kfree(right_response);
+
+ return rv;
+}
+#endif
+
+int drbd_receiver(struct drbd_thread *thi)
+{
+ struct drbd_connection *connection = thi->connection;
+ int h;
+
+ drbd_info(connection, "receiver (re)started\n");
+
+ do {
+ h = conn_connect(connection);
+ if (h == 0) {
+ conn_disconnect(connection);
+ schedule_timeout_interruptible(HZ);
+ }
+ if (h == -1) {
+ drbd_warn(connection, "Discarding network configuration.\n");
+ conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_HARD);
+ }
+ } while (h == 0);
+
+ if (h > 0)
+ drbdd(connection);
+
+ conn_disconnect(connection);
+
+ drbd_info(connection, "receiver terminated\n");
+ return 0;
+}
+
+/* ********* acknowledge sender ******** */
+
+static int got_conn_RqSReply(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct p_req_state_reply *p = pi->data;
+ int retcode = be32_to_cpu(p->retcode);
+
+ if (retcode >= SS_SUCCESS) {
+ set_bit(CONN_WD_ST_CHG_OKAY, &connection->flags);
+ } else {
+ set_bit(CONN_WD_ST_CHG_FAIL, &connection->flags);
+ drbd_err(connection, "Requested state change failed by peer: %s (%d)\n",
+ drbd_set_st_err_str(retcode), retcode);
+ }
+ wake_up(&connection->ping_wait);
+
+ return 0;
+}
+
+static int got_RqSReply(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct drbd_peer_device *peer_device;
+ struct drbd_device *device;
+ struct p_req_state_reply *p = pi->data;
+ int retcode = be32_to_cpu(p->retcode);
+
+ peer_device = conn_peer_device(connection, pi->vnr);
+ if (!peer_device)
+ return -EIO;
+ device = peer_device->device;
+
+ if (test_bit(CONN_WD_ST_CHG_REQ, &connection->flags)) {
+ D_ASSERT(device, connection->agreed_pro_version < 100);
+ return got_conn_RqSReply(connection, pi);
+ }
+
+ if (retcode >= SS_SUCCESS) {
+ set_bit(CL_ST_CHG_SUCCESS, &device->flags);
+ } else {
+ set_bit(CL_ST_CHG_FAIL, &device->flags);
+ drbd_err(device, "Requested state change failed by peer: %s (%d)\n",
+ drbd_set_st_err_str(retcode), retcode);
+ }
+ wake_up(&device->state_wait);
+
+ return 0;
+}
+
+static int got_Ping(struct drbd_connection *connection, struct packet_info *pi)
+{
+ return drbd_send_ping_ack(connection);
+
+}
+
+static int got_PingAck(struct drbd_connection *connection, struct packet_info *pi)
+{
+ /* restore idle timeout */
+ connection->meta.socket->sk->sk_rcvtimeo = connection->net_conf->ping_int*HZ;
+ if (!test_and_set_bit(GOT_PING_ACK, &connection->flags))
+ wake_up(&connection->ping_wait);
+
+ return 0;
+}
+
+static int got_IsInSync(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct drbd_peer_device *peer_device;
+ struct drbd_device *device;
+ struct p_block_ack *p = pi->data;
+ sector_t sector = be64_to_cpu(p->sector);
+ int blksize = be32_to_cpu(p->blksize);
+
+ peer_device = conn_peer_device(connection, pi->vnr);
+ if (!peer_device)
+ return -EIO;
+ device = peer_device->device;
+
+ D_ASSERT(device, peer_device->connection->agreed_pro_version >= 89);
+
+ update_peer_seq(peer_device, be32_to_cpu(p->seq_num));
+
+ if (get_ldev(device)) {
+ drbd_rs_complete_io(device, sector);
+ drbd_set_in_sync(device, sector, blksize);
+ /* rs_same_csums is supposed to count in units of BM_BLOCK_SIZE */
+ device->rs_same_csum += (blksize >> BM_BLOCK_SHIFT);
+ put_ldev(device);
+ }
+ dec_rs_pending(device);
+ atomic_add(blksize >> 9, &device->rs_sect_in);
+
+ return 0;
+}
+
+static int
+validate_req_change_req_state(struct drbd_device *device, u64 id, sector_t sector,
+ struct rb_root *root, const char *func,
+ enum drbd_req_event what, bool missing_ok)
+{
+ struct drbd_request *req;
+ struct bio_and_error m;
+
+ spin_lock_irq(&device->resource->req_lock);
+ req = find_request(device, root, id, sector, missing_ok, func);
+ if (unlikely(!req)) {
+ spin_unlock_irq(&device->resource->req_lock);
+ return -EIO;
+ }
+ __req_mod(req, what, &m);
+ spin_unlock_irq(&device->resource->req_lock);
+
+ if (m.bio)
+ complete_master_bio(device, &m);
+ return 0;
+}
+
+static int got_BlockAck(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct drbd_peer_device *peer_device;
+ struct drbd_device *device;
+ struct p_block_ack *p = pi->data;
+ sector_t sector = be64_to_cpu(p->sector);
+ int blksize = be32_to_cpu(p->blksize);
+ enum drbd_req_event what;
+
+ peer_device = conn_peer_device(connection, pi->vnr);
+ if (!peer_device)
+ return -EIO;
+ device = peer_device->device;
+
+ update_peer_seq(peer_device, be32_to_cpu(p->seq_num));
+
+ if (p->block_id == ID_SYNCER) {
+ drbd_set_in_sync(device, sector, blksize);
+ dec_rs_pending(device);
+ return 0;
+ }
+ switch (pi->cmd) {
+ case P_RS_WRITE_ACK:
+ what = WRITE_ACKED_BY_PEER_AND_SIS;
+ break;
+ case P_WRITE_ACK:
+ what = WRITE_ACKED_BY_PEER;
+ break;
+ case P_RECV_ACK:
+ what = RECV_ACKED_BY_PEER;
+ break;
+ case P_SUPERSEDED:
+ what = CONFLICT_RESOLVED;
+ break;
+ case P_RETRY_WRITE:
+ what = POSTPONE_WRITE;
+ break;
+ default:
+ BUG();
+ }
+
+ return validate_req_change_req_state(device, p->block_id, sector,
+ &device->write_requests, __func__,
+ what, false);
+}
+
+static int got_NegAck(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct drbd_peer_device *peer_device;
+ struct drbd_device *device;
+ struct p_block_ack *p = pi->data;
+ sector_t sector = be64_to_cpu(p->sector);
+ int size = be32_to_cpu(p->blksize);
+ int err;
+
+ peer_device = conn_peer_device(connection, pi->vnr);
+ if (!peer_device)
+ return -EIO;
+ device = peer_device->device;
+
+ update_peer_seq(peer_device, be32_to_cpu(p->seq_num));
+
+ if (p->block_id == ID_SYNCER) {
+ dec_rs_pending(device);
+ drbd_rs_failed_io(device, sector, size);
+ return 0;
+ }
+
+ err = validate_req_change_req_state(device, p->block_id, sector,
+ &device->write_requests, __func__,
+ NEG_ACKED, true);
+ if (err) {
+ /* Protocol A has no P_WRITE_ACKs, but has P_NEG_ACKs.
+ The master bio might already be completed, therefore the
+ request is no longer in the collision hash. */
+ /* In Protocol B we might already have got a P_RECV_ACK
+ but then get a P_NEG_ACK afterwards. */
+ drbd_set_out_of_sync(device, sector, size);
+ }
+ return 0;
+}
+
+static int got_NegDReply(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct drbd_peer_device *peer_device;
+ struct drbd_device *device;
+ struct p_block_ack *p = pi->data;
+ sector_t sector = be64_to_cpu(p->sector);
+
+ peer_device = conn_peer_device(connection, pi->vnr);
+ if (!peer_device)
+ return -EIO;
+ device = peer_device->device;
+
+ update_peer_seq(peer_device, be32_to_cpu(p->seq_num));
+
+ drbd_err(device, "Got NegDReply; Sector %llus, len %u.\n",
+ (unsigned long long)sector, be32_to_cpu(p->blksize));
+
+ return validate_req_change_req_state(device, p->block_id, sector,
+ &device->read_requests, __func__,
+ NEG_ACKED, false);
+}
+
+static int got_NegRSDReply(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct drbd_peer_device *peer_device;
+ struct drbd_device *device;
+ sector_t sector;
+ int size;
+ struct p_block_ack *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);
+ size = be32_to_cpu(p->blksize);
+
+ update_peer_seq(peer_device, be32_to_cpu(p->seq_num));
+
+ dec_rs_pending(device);
+
+ if (get_ldev_if_state(device, D_FAILED)) {
+ drbd_rs_complete_io(device, sector);
+ switch (pi->cmd) {
+ case P_NEG_RS_DREPLY:
+ drbd_rs_failed_io(device, sector, size);
+ case P_RS_CANCEL:
+ break;
+ default:
+ BUG();
+ }
+ put_ldev(device);
+ }
+
+ return 0;
+}
+
+static int got_BarrierAck(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct p_barrier_ack *p = pi->data;
+ struct drbd_peer_device *peer_device;
+ int vnr;
+
+ tl_release(connection, p->barrier, be32_to_cpu(p->set_size));
+
+ rcu_read_lock();
+ idr_for_each_entry(&connection->peer_devices, peer_device, vnr) {
+ struct drbd_device *device = peer_device->device;
+
+ if (device->state.conn == C_AHEAD &&
+ atomic_read(&device->ap_in_flight) == 0 &&
+ !test_and_set_bit(AHEAD_TO_SYNC_SOURCE, &device->flags)) {
+ device->start_resync_timer.expires = jiffies + HZ;
+ add_timer(&device->start_resync_timer);
+ }
+ }
+ rcu_read_unlock();
+
+ return 0;
+}
+
+static int got_OVResult(struct drbd_connection *connection, struct packet_info *pi)
+{
+ struct drbd_peer_device *peer_device;
+ struct drbd_device *device;
+ struct p_block_ack *p = pi->data;
+ struct drbd_device_work *dw;
+ sector_t sector;
+ int size;
+
+ peer_device = conn_peer_device(connection, pi->vnr);
+ if (!peer_device)
+ return -EIO;
+ device = peer_device->device;
+
+ sector = be64_to_cpu(p->sector);
+ size = be32_to_cpu(p->blksize);
+
+ update_peer_seq(peer_device, be32_to_cpu(p->seq_num));
+
+ if (be64_to_cpu(p->block_id) == ID_OUT_OF_SYNC)
+ drbd_ov_out_of_sync_found(device, sector, size);
+ else
+ ov_out_of_sync_print(device);
+
+ if (!get_ldev(device))
+ return 0;
+
+ drbd_rs_complete_io(device, sector);
+ dec_rs_pending(device);
+
+ --device->ov_left;
+
+ /* let's advance progress step marks only for every other megabyte */
+ if ((device->ov_left & 0x200) == 0x200)
+ drbd_advance_rs_marks(device, device->ov_left);
+
+ if (device->ov_left == 0) {
+ dw = kmalloc(sizeof(*dw), GFP_NOIO);
+ if (dw) {
+ dw->w.cb = w_ov_finished;
+ dw->device = device;
+ drbd_queue_work(&peer_device->connection->sender_work, &dw->w);
+ } else {
+ drbd_err(device, "kmalloc(dw) failed.");
+ ov_out_of_sync_print(device);
+ drbd_resync_finished(device);
+ }
+ }
+ put_ldev(device);
+ return 0;
+}
+
+static int got_skip(struct drbd_connection *connection, struct packet_info *pi)
+{
+ return 0;
+}
+
+static int connection_finish_peer_reqs(struct drbd_connection *connection)
+{
+ struct drbd_peer_device *peer_device;
+ int vnr, not_empty = 0;
+
+ do {
+ clear_bit(SIGNAL_ASENDER, &connection->flags);
+ flush_signals(current);
+
+ 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 (drbd_finish_peer_reqs(device)) {
+ kref_put(&device->kref, drbd_destroy_device);
+ return 1;
+ }
+ kref_put(&device->kref, drbd_destroy_device);
+ rcu_read_lock();
+ }
+ set_bit(SIGNAL_ASENDER, &connection->flags);
+
+ spin_lock_irq(&connection->resource->req_lock);
+ idr_for_each_entry(&connection->peer_devices, peer_device, vnr) {
+ struct drbd_device *device = peer_device->device;
+ not_empty = !list_empty(&device->done_ee);
+ if (not_empty)
+ break;
+ }
+ spin_unlock_irq(&connection->resource->req_lock);
+ rcu_read_unlock();
+ } while (not_empty);
+
+ return 0;
+}
+
+struct asender_cmd {
+ size_t pkt_size;
+ int (*fn)(struct drbd_connection *connection, struct packet_info *);
+};
+
+static struct asender_cmd asender_tbl[] = {
+ [P_PING] = { 0, got_Ping },
+ [P_PING_ACK] = { 0, got_PingAck },
+ [P_RECV_ACK] = { sizeof(struct p_block_ack), got_BlockAck },
+ [P_WRITE_ACK] = { sizeof(struct p_block_ack), got_BlockAck },
+ [P_RS_WRITE_ACK] = { sizeof(struct p_block_ack), got_BlockAck },
+ [P_SUPERSEDED] = { sizeof(struct p_block_ack), got_BlockAck },
+ [P_NEG_ACK] = { sizeof(struct p_block_ack), got_NegAck },
+ [P_NEG_DREPLY] = { sizeof(struct p_block_ack), got_NegDReply },
+ [P_NEG_RS_DREPLY] = { sizeof(struct p_block_ack), got_NegRSDReply },
+ [P_OV_RESULT] = { sizeof(struct p_block_ack), got_OVResult },
+ [P_BARRIER_ACK] = { sizeof(struct p_barrier_ack), got_BarrierAck },
+ [P_STATE_CHG_REPLY] = { sizeof(struct p_req_state_reply), got_RqSReply },
+ [P_RS_IS_IN_SYNC] = { sizeof(struct p_block_ack), got_IsInSync },
+ [P_DELAY_PROBE] = { sizeof(struct p_delay_probe93), got_skip },
+ [P_RS_CANCEL] = { sizeof(struct p_block_ack), got_NegRSDReply },
+ [P_CONN_ST_CHG_REPLY]={ sizeof(struct p_req_state_reply), got_conn_RqSReply },
+ [P_RETRY_WRITE] = { sizeof(struct p_block_ack), got_BlockAck },
+};
+
+int drbd_asender(struct drbd_thread *thi)
+{
+ struct drbd_connection *connection = thi->connection;
+ struct asender_cmd *cmd = NULL;
+ struct packet_info pi;
+ int rv;
+ void *buf = connection->meta.rbuf;
+ int received = 0;
+ unsigned int header_size = drbd_header_size(connection);
+ int expect = header_size;
+ bool ping_timeout_active = false;
+ struct net_conf *nc;
+ int ping_timeo, tcp_cork, ping_int;
+ struct sched_param param = { .sched_priority = 2 };
+
+ rv = sched_setscheduler(current, SCHED_RR, &param);
+ if (rv < 0)
+ drbd_err(connection, "drbd_asender: ERROR set priority, ret=%d\n", rv);
+
+ while (get_t_state(thi) == RUNNING) {
+ drbd_thread_current_set_cpu(thi);
+
+ rcu_read_lock();
+ nc = rcu_dereference(connection->net_conf);
+ ping_timeo = nc->ping_timeo;
+ tcp_cork = nc->tcp_cork;
+ ping_int = nc->ping_int;
+ rcu_read_unlock();
+
+ if (test_and_clear_bit(SEND_PING, &connection->flags)) {
+ if (drbd_send_ping(connection)) {
+ drbd_err(connection, "drbd_send_ping has failed\n");
+ goto reconnect;
+ }
+ connection->meta.socket->sk->sk_rcvtimeo = ping_timeo * HZ / 10;
+ ping_timeout_active = true;
+ }
+
+ /* TODO: conditionally cork; it may hurt latency if we cork without
+ much to send */
+ if (tcp_cork)
+ drbd_tcp_cork(connection->meta.socket);
+ if (connection_finish_peer_reqs(connection)) {
+ drbd_err(connection, "connection_finish_peer_reqs() failed\n");
+ goto reconnect;
+ }
+ /* but unconditionally uncork unless disabled */
+ if (tcp_cork)
+ drbd_tcp_uncork(connection->meta.socket);
+
+ /* short circuit, recv_msg would return EINTR anyways. */
+ if (signal_pending(current))
+ continue;
+
+ rv = drbd_recv_short(connection->meta.socket, buf, expect-received, 0);
+ clear_bit(SIGNAL_ASENDER, &connection->flags);
+
+ flush_signals(current);
+
+ /* Note:
+ * -EINTR (on meta) we got a signal
+ * -EAGAIN (on meta) rcvtimeo expired
+ * -ECONNRESET other side closed the connection
+ * -ERESTARTSYS (on data) we got a signal
+ * rv < 0 other than above: unexpected error!
+ * rv == expected: full header or command
+ * rv < expected: "woken" by signal during receive
+ * rv == 0 : "connection shut down by peer"
+ */
+received_more:
+ if (likely(rv > 0)) {
+ received += rv;
+ buf += 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)
+ break;
+ }
+ drbd_err(connection, "meta connection shut down by peer.\n");
+ goto reconnect;
+ } else if (rv == -EAGAIN) {
+ /* If the data socket received something meanwhile,
+ * that is good enough: peer is still alive. */
+ if (time_after(connection->last_received,
+ jiffies - connection->meta.socket->sk->sk_rcvtimeo))
+ continue;
+ if (ping_timeout_active) {
+ drbd_err(connection, "PingAck did not arrive in time.\n");
+ goto reconnect;
+ }
+ set_bit(SEND_PING, &connection->flags);
+ continue;
+ } else if (rv == -EINTR) {
+ continue;
+ } else {
+ drbd_err(connection, "sock_recvmsg returned %d\n", rv);
+ goto reconnect;
+ }
+
+ if (received == expect && cmd == NULL) {
+ if (decode_header(connection, connection->meta.rbuf, &pi))
+ goto reconnect;
+ cmd = &asender_tbl[pi.cmd];
+ if (pi.cmd >= ARRAY_SIZE(asender_tbl) || !cmd->fn) {
+ drbd_err(connection, "Unexpected meta packet %s (0x%04x)\n",
+ cmdname(pi.cmd), pi.cmd);
+ goto disconnect;
+ }
+ expect = header_size + cmd->pkt_size;
+ if (pi.size != expect - header_size) {
+ drbd_err(connection, "Wrong packet size on meta (c: %d, l: %d)\n",
+ pi.cmd, pi.size);
+ goto reconnect;
+ }
+ }
+ if (received == expect) {
+ bool err;
+
+ err = cmd->fn(connection, &pi);
+ if (err) {
+ drbd_err(connection, "%pf failed\n", cmd->fn);
+ goto reconnect;
+ }
+
+ connection->last_received = jiffies;
+
+ if (cmd == &asender_tbl[P_PING_ACK]) {
+ /* restore idle timeout */
+ connection->meta.socket->sk->sk_rcvtimeo = ping_int * HZ;
+ ping_timeout_active = false;
+ }
+
+ buf = connection->meta.rbuf;
+ received = 0;
+ expect = header_size;
+ cmd = NULL;
+ }
+ if (test_bit(SEND_PING, &connection->flags))
+ continue;
+ rv = drbd_recv_short(connection->meta.socket, buf, expect-received, MSG_DONTWAIT);
+ if (rv > 0)
+ goto received_more;
+ }
+
+ if (0) {
+reconnect:
+ conn_request_state(connection, NS(conn, C_NETWORK_FAILURE), CS_HARD);
+ conn_md_sync(connection);
+ }
+ if (0) {
+disconnect:
+ conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_HARD);
+ }
+ clear_bit(SIGNAL_ASENDER, &connection->flags);
+
+ drbd_info(connection, "asender terminated\n");
+
+ return 0;
+}