drbd_receiver.c 150.6 KB
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/*
   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"
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#include "drbd_protocol.h"
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#include "drbd_req.h"

#include "drbd_vli.h"

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struct packet_info {
	enum drbd_packet cmd;
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	unsigned int size;
	unsigned int vnr;
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	void *data;
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};

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enum finish_epoch {
	FE_STILL_LIVE,
	FE_DESTROYED,
	FE_RECYCLED,
};

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static int drbd_do_features(struct drbd_connection *connection);
static int drbd_do_auth(struct drbd_connection *connection);
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static int drbd_disconnected(struct drbd_device *device);
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static enum finish_epoch drbd_may_finish_epoch(struct drbd_connection *, struct drbd_epoch *, enum epoch_event);
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static int e_end_block(struct drbd_work *, int);
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#define GFP_TRY	(__GFP_HIGHMEM | __GFP_NOWARN)

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/*
 * 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;
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	if (!page)
		return NULL;

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	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;
}

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static struct page *__drbd_alloc_pages(struct drbd_device *device,
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				       unsigned int number)
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{
	struct page *page = NULL;
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	struct page *tmp = NULL;
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	unsigned int i = 0;
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	/* Yes, testing drbd_pp_vacant outside the lock is racy.
	 * So what. It saves a spin_lock. */
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	if (drbd_pp_vacant >= number) {
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		spin_lock(&drbd_pp_lock);
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		page = page_chain_del(&drbd_pp_pool, number);
		if (page)
			drbd_pp_vacant -= number;
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		spin_unlock(&drbd_pp_lock);
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		if (page)
			return page;
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	}
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	/* 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.  */
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	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.
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	 * No need to jump around here, drbd_alloc_pages will retry this
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	 * 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;
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}

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static void reclaim_finished_net_peer_reqs(struct drbd_device *device,
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					   struct list_head *to_be_freed)
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{
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	struct drbd_peer_request *peer_req;
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	struct list_head *le, *tle;

	/* 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... */

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	list_for_each_safe(le, tle, &device->net_ee) {
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		peer_req = list_entry(le, struct drbd_peer_request, w.list);
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		if (drbd_peer_req_has_active_page(peer_req))
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			break;
		list_move(le, to_be_freed);
	}
}

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static void drbd_kick_lo_and_reclaim_net(struct drbd_device *device)
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{
	LIST_HEAD(reclaimed);
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	struct drbd_peer_request *peer_req, *t;
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	spin_lock_irq(&device->connection->req_lock);
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	reclaim_finished_net_peer_reqs(device, &reclaimed);
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	spin_unlock_irq(&device->connection->req_lock);
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	list_for_each_entry_safe(peer_req, t, &reclaimed, w.list)
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		drbd_free_net_peer_req(device, peer_req);
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}

/**
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 * drbd_alloc_pages() - Returns @number pages, retries forever (or until signalled)
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 * @device:	DRBD device.
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 * @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, unless this allocation would exceed the max_buffers setting.
 * Possibly retry until DRBD frees sufficient pages somewhere else.
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 *
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 * Returns a page chain linked via page->private.
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 */
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struct page *drbd_alloc_pages(struct drbd_device *device, unsigned int number,
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			      bool retry)
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{
	struct page *page = NULL;
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	struct net_conf *nc;
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	DEFINE_WAIT(wait);
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	int mxb;
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	/* Yes, we may run up to @number over max_buffers. If we
	 * follow it strictly, the admin will get it wrong anyways. */
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	rcu_read_lock();
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	nc = rcu_dereference(device->connection->net_conf);
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	mxb = nc ? nc->max_buffers : 1000000;
	rcu_read_unlock();

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	if (atomic_read(&device->pp_in_use) < mxb)
		page = __drbd_alloc_pages(device, number);
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	while (page == NULL) {
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		prepare_to_wait(&drbd_pp_wait, &wait, TASK_INTERRUPTIBLE);

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		drbd_kick_lo_and_reclaim_net(device);
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		if (atomic_read(&device->pp_in_use) < mxb) {
			page = __drbd_alloc_pages(device, number);
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			if (page)
				break;
		}

		if (!retry)
			break;

		if (signal_pending(current)) {
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			dev_warn(DEV, "drbd_alloc_pages interrupted!\n");
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			break;
		}

		schedule();
	}
	finish_wait(&drbd_pp_wait, &wait);

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	if (page)
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		atomic_add(number, &device->pp_in_use);
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	return page;
}

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/* Must not be used from irq, as that may deadlock: see drbd_alloc_pages.
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 * Is also used from inside an other spin_lock_irq(&device->connection->req_lock);
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 * Either links the page chain back to the global pool,
 * or returns all pages to the system. */
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static void drbd_free_pages(struct drbd_device *device, struct page *page, int is_net)
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{
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	atomic_t *a = is_net ? &device->pp_in_use_by_net : &device->pp_in_use;
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	int i;
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	if (page == NULL)
		return;

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	if (drbd_pp_vacant > (DRBD_MAX_BIO_SIZE/PAGE_SIZE) * minor_count)
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		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);
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	}
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	i = atomic_sub_return(i, a);
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	if (i < 0)
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		dev_warn(DEV, "ASSERTION FAILED: %s: %d < 0\n",
			is_net ? "pp_in_use_by_net" : "pp_in_use", i);
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	wake_up(&drbd_pp_wait);
}

/*
You need to hold the req_lock:
 _drbd_wait_ee_list_empty()

You must not have the req_lock:
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 drbd_free_peer_req()
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 drbd_alloc_peer_req()
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 drbd_free_peer_reqs()
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 drbd_ee_fix_bhs()
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 drbd_finish_peer_reqs()
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 drbd_clear_done_ee()
 drbd_wait_ee_list_empty()
*/

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struct drbd_peer_request *
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drbd_alloc_peer_req(struct drbd_device *device, u64 id, sector_t sector,
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		    unsigned int data_size, gfp_t gfp_mask) __must_hold(local)
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{
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	struct drbd_peer_request *peer_req;
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	struct page *page = NULL;
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	unsigned nr_pages = (data_size + PAGE_SIZE -1) >> PAGE_SHIFT;
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	if (drbd_insert_fault(device, DRBD_FAULT_AL_EE))
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		return NULL;

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	peer_req = mempool_alloc(drbd_ee_mempool, gfp_mask & ~__GFP_HIGHMEM);
	if (!peer_req) {
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		if (!(gfp_mask & __GFP_NOWARN))
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			dev_err(DEV, "%s: allocation failed\n", __func__);
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		return NULL;
	}

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	if (data_size) {
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		page = drbd_alloc_pages(device, nr_pages, (gfp_mask & __GFP_WAIT));
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		if (!page)
			goto fail;
	}
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	drbd_clear_interval(&peer_req->i);
	peer_req->i.size = data_size;
	peer_req->i.sector = sector;
	peer_req->i.local = false;
	peer_req->i.waiting = false;

	peer_req->epoch = NULL;
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	peer_req->w.device = device;
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	peer_req->pages = page;
	atomic_set(&peer_req->pending_bios, 0);
	peer_req->flags = 0;
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	/*
	 * The block_id is opaque to the receiver.  It is not endianness
	 * converted, and sent back to the sender unchanged.
	 */
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	peer_req->block_id = id;
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	return peer_req;
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 fail:
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	mempool_free(peer_req, drbd_ee_mempool);
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	return NULL;
}

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void __drbd_free_peer_req(struct drbd_device *device, struct drbd_peer_request *peer_req,
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		       int is_net)
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{
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	if (peer_req->flags & EE_HAS_DIGEST)
		kfree(peer_req->digest);
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	drbd_free_pages(device, peer_req->pages, is_net);
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	D_ASSERT(atomic_read(&peer_req->pending_bios) == 0);
	D_ASSERT(drbd_interval_empty(&peer_req->i));
	mempool_free(peer_req, drbd_ee_mempool);
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}

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int drbd_free_peer_reqs(struct drbd_device *device, struct list_head *list)
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{
	LIST_HEAD(work_list);
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	struct drbd_peer_request *peer_req, *t;
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	int count = 0;
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	int is_net = list == &device->net_ee;
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	spin_lock_irq(&device->connection->req_lock);
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	list_splice_init(list, &work_list);
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	spin_unlock_irq(&device->connection->req_lock);
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	list_for_each_entry_safe(peer_req, t, &work_list, w.list) {
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		__drbd_free_peer_req(device, peer_req, is_net);
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		count++;
	}
	return count;
}

/*
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 * See also comments in _req_mod(,BARRIER_ACKED) and receive_Barrier.
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 */
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static int drbd_finish_peer_reqs(struct drbd_device *device)
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{
	LIST_HEAD(work_list);
	LIST_HEAD(reclaimed);
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	struct drbd_peer_request *peer_req, *t;
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	int err = 0;
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	spin_lock_irq(&device->connection->req_lock);
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	reclaim_finished_net_peer_reqs(device, &reclaimed);
	list_splice_init(&device->done_ee, &work_list);
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	spin_unlock_irq(&device->connection->req_lock);
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	list_for_each_entry_safe(peer_req, t, &reclaimed, w.list)
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		drbd_free_net_peer_req(device, peer_req);
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	/* possible callbacks here:
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	 * e_end_block, and e_end_resync_block, e_send_superseded.
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	 * all ignore the last argument.
	 */
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	list_for_each_entry_safe(peer_req, t, &work_list, w.list) {
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		int err2;

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		/* list_del not necessary, next/prev members not touched */
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		err2 = peer_req->w.cb(&peer_req->w, !!err);
		if (!err)
			err = err2;
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		drbd_free_peer_req(device, peer_req);
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	}
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	wake_up(&device->ee_wait);
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	return err;
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}

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static void _drbd_wait_ee_list_empty(struct drbd_device *device,
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				     struct list_head *head)
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{
	DEFINE_WAIT(wait);

	/* avoids spin_lock/unlock
	 * and calling prepare_to_wait in the fast path */
	while (!list_empty(head)) {
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		prepare_to_wait(&device->ee_wait, &wait, TASK_UNINTERRUPTIBLE);
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		spin_unlock_irq(&device->connection->req_lock);
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		io_schedule();
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		finish_wait(&device->ee_wait, &wait);
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		spin_lock_irq(&device->connection->req_lock);
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	}
}

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static void drbd_wait_ee_list_empty(struct drbd_device *device,
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				    struct list_head *head)
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{
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	spin_lock_irq(&device->connection->req_lock);
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	_drbd_wait_ee_list_empty(device, head);
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	spin_unlock_irq(&device->connection->req_lock);
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}

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static int drbd_recv_short(struct socket *sock, void *buf, size_t size, int flags)
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{
	mm_segment_t oldfs;
	struct kvec iov = {
		.iov_base = buf,
		.iov_len = size,
	};
	struct msghdr msg = {
		.msg_iovlen = 1,
		.msg_iov = (struct iovec *)&iov,
		.msg_flags = (flags ? flags : MSG_WAITALL | MSG_NOSIGNAL)
	};
	int rv;

	oldfs = get_fs();
	set_fs(KERNEL_DS);
	rv = sock_recvmsg(sock, &msg, size, msg.msg_flags);
	set_fs(oldfs);

	return rv;
}

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static int drbd_recv(struct drbd_connection *connection, void *buf, size_t size)
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{
	int rv;

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	rv = drbd_recv_short(connection->data.socket, buf, size, 0);
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	if (rv < 0) {
		if (rv == -ECONNRESET)
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			conn_info(connection, "sock was reset by peer\n");
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		else if (rv != -ERESTARTSYS)
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			conn_err(connection, "sock_recvmsg returned %d\n", rv);
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	} else if (rv == 0) {
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		if (test_bit(DISCONNECT_SENT, &connection->flags)) {
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			long t;
			rcu_read_lock();
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			t = rcu_dereference(connection->net_conf)->ping_timeo * HZ/10;
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			rcu_read_unlock();

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			t = wait_event_timeout(connection->ping_wait, connection->cstate < C_WF_REPORT_PARAMS, t);
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			if (t)
				goto out;
		}
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		conn_info(connection, "sock was shut down by peer\n");
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	}

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	if (rv != size)
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		conn_request_state(connection, NS(conn, C_BROKEN_PIPE), CS_HARD);
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out:
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	return rv;
}

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static int drbd_recv_all(struct drbd_connection *connection, void *buf, size_t size)
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{
	int err;

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	err = drbd_recv(connection, buf, size);
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	if (err != size) {
		if (err >= 0)
			err = -EIO;
	} else
		err = 0;
	return err;
}

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static int drbd_recv_all_warn(struct drbd_connection *connection, void *buf, size_t size)
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{
	int err;

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	err = drbd_recv_all(connection, buf, size);
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	if (err && !signal_pending(current))
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		conn_warn(connection, "short read (expected size %d)\n", (int)size);
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	return err;
}

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/* 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;
	}
}

567
static struct socket *drbd_try_connect(struct drbd_connection *connection)
P
Philipp Reisner 已提交
568 569 570 571
{
	const char *what;
	struct socket *sock;
	struct sockaddr_in6 src_in6;
572 573 574
	struct sockaddr_in6 peer_in6;
	struct net_conf *nc;
	int err, peer_addr_len, my_addr_len;
575
	int sndbuf_size, rcvbuf_size, connect_int;
P
Philipp Reisner 已提交
576 577
	int disconnect_on_error = 1;

578
	rcu_read_lock();
579
	nc = rcu_dereference(connection->net_conf);
580 581
	if (!nc) {
		rcu_read_unlock();
P
Philipp Reisner 已提交
582
		return NULL;
583 584 585
	}
	sndbuf_size = nc->sndbuf_size;
	rcvbuf_size = nc->rcvbuf_size;
586
	connect_int = nc->connect_int;
587
	rcu_read_unlock();
588

589 590
	my_addr_len = min_t(int, connection->my_addr_len, sizeof(src_in6));
	memcpy(&src_in6, &connection->my_addr, my_addr_len);
591

592
	if (((struct sockaddr *)&connection->my_addr)->sa_family == AF_INET6)
593 594 595 596
		src_in6.sin6_port = 0;
	else
		((struct sockaddr_in *)&src_in6)->sin_port = 0; /* AF_INET & AF_SCI */

597 598
	peer_addr_len = min_t(int, connection->peer_addr_len, sizeof(src_in6));
	memcpy(&peer_in6, &connection->peer_addr, peer_addr_len);
P
Philipp Reisner 已提交
599 600

	what = "sock_create_kern";
601 602
	err = sock_create_kern(((struct sockaddr *)&src_in6)->sa_family,
			       SOCK_STREAM, IPPROTO_TCP, &sock);
P
Philipp Reisner 已提交
603 604 605 606 607 608
	if (err < 0) {
		sock = NULL;
		goto out;
	}

	sock->sk->sk_rcvtimeo =
609
	sock->sk->sk_sndtimeo = connect_int * HZ;
610
	drbd_setbufsize(sock, sndbuf_size, rcvbuf_size);
P
Philipp Reisner 已提交
611 612 613 614 615 616 617 618 619

       /* 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";
620
	err = sock->ops->bind(sock, (struct sockaddr *) &src_in6, my_addr_len);
P
Philipp Reisner 已提交
621 622 623 624 625 626 627
	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";
628
	err = sock->ops->connect(sock, (struct sockaddr *) &peer_in6, peer_addr_len, 0);
P
Philipp Reisner 已提交
629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645

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:
646
			conn_err(connection, "%s failed, err = %d\n", what, err);
P
Philipp Reisner 已提交
647 648
		}
		if (disconnect_on_error)
649
			conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_HARD);
P
Philipp Reisner 已提交
650
	}
651

P
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652 653 654
	return sock;
}

655
struct accept_wait_data {
656
	struct drbd_connection *connection;
657 658 659 660 661 662
	struct socket *s_listen;
	struct completion door_bell;
	void (*original_sk_state_change)(struct sock *sk);

};

663
static void drbd_incoming_connection(struct sock *sk)
664 665
{
	struct accept_wait_data *ad = sk->sk_user_data;
666
	void (*state_change)(struct sock *sk);
667

668 669 670 671
	state_change = ad->original_sk_state_change;
	if (sk->sk_state == TCP_ESTABLISHED)
		complete(&ad->door_bell);
	state_change(sk);
672 673
}

674
static int prepare_listen_socket(struct drbd_connection *connection, struct accept_wait_data *ad)
P
Philipp Reisner 已提交
675
{
676
	int err, sndbuf_size, rcvbuf_size, my_addr_len;
677
	struct sockaddr_in6 my_addr;
678
	struct socket *s_listen;
679
	struct net_conf *nc;
P
Philipp Reisner 已提交
680 681
	const char *what;

682
	rcu_read_lock();
683
	nc = rcu_dereference(connection->net_conf);
684 685
	if (!nc) {
		rcu_read_unlock();
686
		return -EIO;
687 688 689 690
	}
	sndbuf_size = nc->sndbuf_size;
	rcvbuf_size = nc->rcvbuf_size;
	rcu_read_unlock();
P
Philipp Reisner 已提交
691

692 693
	my_addr_len = min_t(int, connection->my_addr_len, sizeof(struct sockaddr_in6));
	memcpy(&my_addr, &connection->my_addr, my_addr_len);
P
Philipp Reisner 已提交
694 695

	what = "sock_create_kern";
696
	err = sock_create_kern(((struct sockaddr *)&my_addr)->sa_family,
697
			       SOCK_STREAM, IPPROTO_TCP, &s_listen);
P
Philipp Reisner 已提交
698 699 700 701 702
	if (err) {
		s_listen = NULL;
		goto out;
	}

703
	s_listen->sk->sk_reuse = SK_CAN_REUSE; /* SO_REUSEADDR */
704
	drbd_setbufsize(s_listen, sndbuf_size, rcvbuf_size);
P
Philipp Reisner 已提交
705 706

	what = "bind before listen";
707
	err = s_listen->ops->bind(s_listen, (struct sockaddr *)&my_addr, my_addr_len);
P
Philipp Reisner 已提交
708 709 710
	if (err < 0)
		goto out;

711 712 713
	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;
714
	s_listen->sk->sk_state_change = drbd_incoming_connection;
715 716
	s_listen->sk->sk_user_data = ad;
	write_unlock_bh(&s_listen->sk->sk_callback_lock);
P
Philipp Reisner 已提交
717

718 719 720 721 722
	what = "listen";
	err = s_listen->ops->listen(s_listen, 5);
	if (err < 0)
		goto out;

723
	return 0;
P
Philipp Reisner 已提交
724 725 726 727 728
out:
	if (s_listen)
		sock_release(s_listen);
	if (err < 0) {
		if (err != -EAGAIN && err != -EINTR && err != -ERESTARTSYS) {
729 730
			conn_err(connection, "%s failed, err = %d\n", what, err);
			conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_HARD);
P
Philipp Reisner 已提交
731 732 733
		}
	}

734
	return -EIO;
P
Philipp Reisner 已提交
735 736
}

737
static void unregister_state_change(struct sock *sk, struct accept_wait_data *ad)
P
Philipp Reisner 已提交
738
{
739 740 741 742
	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);
P
Philipp Reisner 已提交
743 744
}

745
static struct socket *drbd_wait_for_connect(struct drbd_connection *connection, struct accept_wait_data *ad)
P
Philipp Reisner 已提交
746
{
747 748 749 750 751
	int timeo, connect_int, err = 0;
	struct socket *s_estab = NULL;
	struct net_conf *nc;

	rcu_read_lock();
752
	nc = rcu_dereference(connection->net_conf);
753 754 755 756 757 758 759 760
	if (!nc) {
		rcu_read_unlock();
		return NULL;
	}
	connect_int = nc->connect_int;
	rcu_read_unlock();

	timeo = connect_int * HZ;
761 762
	/* 28.5% random jitter */
	timeo += (prandom_u32() & 1) ? timeo / 7 : -timeo / 7;
763

764 765 766
	err = wait_for_completion_interruptible_timeout(&ad->door_bell, timeo);
	if (err <= 0)
		return NULL;
P
Philipp Reisner 已提交
767

768
	err = kernel_accept(ad->s_listen, &s_estab, 0);
P
Philipp Reisner 已提交
769 770
	if (err < 0) {
		if (err != -EAGAIN && err != -EINTR && err != -ERESTARTSYS) {
771 772
			conn_err(connection, "accept failed, err = %d\n", err);
			conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_HARD);
P
Philipp Reisner 已提交
773 774 775
		}
	}

776 777
	if (s_estab)
		unregister_state_change(s_estab->sk, ad);
P
Philipp Reisner 已提交
778 779 780 781

	return s_estab;
}

782
static int decode_header(struct drbd_connection *, void *, struct packet_info *);
P
Philipp Reisner 已提交
783

784
static int send_first_packet(struct drbd_connection *connection, struct drbd_socket *sock,
785 786
			     enum drbd_packet cmd)
{
787
	if (!conn_prepare_command(connection, sock))
788
		return -EIO;
789
	return conn_send_command(connection, sock, cmd, 0, NULL, 0);
P
Philipp Reisner 已提交
790 791
}

792
static int receive_first_packet(struct drbd_connection *connection, struct socket *sock)
P
Philipp Reisner 已提交
793
{
794
	unsigned int header_size = drbd_header_size(connection);
795 796
	struct packet_info pi;
	int err;
P
Philipp Reisner 已提交
797

798
	err = drbd_recv_short(sock, connection->data.rbuf, header_size, 0);
799 800 801 802 803
	if (err != header_size) {
		if (err >= 0)
			err = -EIO;
		return err;
	}
804
	err = decode_header(connection, connection->data.rbuf, &pi);
805 806 807
	if (err)
		return err;
	return pi.cmd;
P
Philipp Reisner 已提交
808 809 810 811 812 813
}

/**
 * drbd_socket_okay() - Free the socket if its connection is not okay
 * @sock:	pointer to the pointer to the socket.
 */
814
static int drbd_socket_okay(struct socket **sock)
P
Philipp Reisner 已提交
815 816 817 818 819
{
	int rr;
	char tb[4];

	if (!*sock)
820
		return false;
P
Philipp Reisner 已提交
821

822
	rr = drbd_recv_short(*sock, tb, 4, MSG_DONTWAIT | MSG_PEEK);
P
Philipp Reisner 已提交
823 824

	if (rr > 0 || rr == -EAGAIN) {
825
		return true;
P
Philipp Reisner 已提交
826 827 828
	} else {
		sock_release(*sock);
		*sock = NULL;
829
		return false;
P
Philipp Reisner 已提交
830 831
	}
}
832 833
/* Gets called if a connection is established, or if a new minor gets created
   in a connection */
834
int drbd_connected(struct drbd_device *device)
835
{
836
	int err;
837

838 839
	atomic_set(&device->packet_seq, 0);
	device->peer_seq = 0;
840

841 842
	device->state_mutex = device->connection->agreed_pro_version < 100 ?
		&device->connection->cstate_mutex :
843
		&device->own_state_mutex;
844

845
	err = drbd_send_sync_param(device);
846
	if (!err)
847
		err = drbd_send_sizes(device, 0, 0);
848
	if (!err)
849
		err = drbd_send_uuids(device);
850
	if (!err)
851 852 853 854 855
		err = drbd_send_current_state(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. */
856
	return err;
857
}
P
Philipp Reisner 已提交
858 859 860 861 862 863 864 865 866

/*
 * 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...
 */
867
static int conn_connect(struct drbd_connection *connection)
P
Philipp Reisner 已提交
868
{
869
	struct drbd_socket sock, msock;
870
	struct drbd_device *device;
871
	struct net_conf *nc;
872
	int vnr, timeout, h, ok;
873
	bool discard_my_data;
874
	enum drbd_state_rv rv;
875
	struct accept_wait_data ad = {
876
		.connection = connection,
877 878
		.door_bell = COMPLETION_INITIALIZER_ONSTACK(ad.door_bell),
	};
P
Philipp Reisner 已提交
879

880 881
	clear_bit(DISCONNECT_SENT, &connection->flags);
	if (conn_request_state(connection, NS(conn, C_WF_CONNECTION), CS_VERBOSE) < SS_SUCCESS)
P
Philipp Reisner 已提交
882 883
		return -2;

884
	mutex_init(&sock.mutex);
885 886
	sock.sbuf = connection->data.sbuf;
	sock.rbuf = connection->data.rbuf;
887 888
	sock.socket = NULL;
	mutex_init(&msock.mutex);
889 890
	msock.sbuf = connection->meta.sbuf;
	msock.rbuf = connection->meta.rbuf;
891 892
	msock.socket = NULL;

893
	/* Assume that the peer only understands protocol 80 until we know better.  */
894
	connection->agreed_pro_version = 80;
P
Philipp Reisner 已提交
895

896
	if (prepare_listen_socket(connection, &ad))
897
		return 0;
P
Philipp Reisner 已提交
898 899

	do {
900
		struct socket *s;
P
Philipp Reisner 已提交
901

902
		s = drbd_try_connect(connection);
P
Philipp Reisner 已提交
903
		if (s) {
904 905
			if (!sock.socket) {
				sock.socket = s;
906
				send_first_packet(connection, &sock, P_INITIAL_DATA);
907
			} else if (!msock.socket) {
908
				clear_bit(RESOLVE_CONFLICTS, &connection->flags);
909
				msock.socket = s;
910
				send_first_packet(connection, &msock, P_INITIAL_META);
P
Philipp Reisner 已提交
911
			} else {
912
				conn_err(connection, "Logic error in conn_connect()\n");
P
Philipp Reisner 已提交
913 914 915 916
				goto out_release_sockets;
			}
		}

917 918
		if (sock.socket && msock.socket) {
			rcu_read_lock();
919
			nc = rcu_dereference(connection->net_conf);
920 921 922 923 924
			timeout = nc->ping_timeo * HZ / 10;
			rcu_read_unlock();
			schedule_timeout_interruptible(timeout);
			ok = drbd_socket_okay(&sock.socket);
			ok = drbd_socket_okay(&msock.socket) && ok;
P
Philipp Reisner 已提交
925 926 927 928 929
			if (ok)
				break;
		}

retry:
930
		s = drbd_wait_for_connect(connection, &ad);
P
Philipp Reisner 已提交
931
		if (s) {
932
			int fp = receive_first_packet(connection, s);
933 934
			drbd_socket_okay(&sock.socket);
			drbd_socket_okay(&msock.socket);
935
			switch (fp) {
936
			case P_INITIAL_DATA:
937
				if (sock.socket) {
938
					conn_warn(connection, "initial packet S crossed\n");
939
					sock_release(sock.socket);
940 941
					sock.socket = s;
					goto randomize;
P
Philipp Reisner 已提交
942
				}
943
				sock.socket = s;
P
Philipp Reisner 已提交
944
				break;
945
			case P_INITIAL_META:
946
				set_bit(RESOLVE_CONFLICTS, &connection->flags);
947
				if (msock.socket) {
948
					conn_warn(connection, "initial packet M crossed\n");
949
					sock_release(msock.socket);
950 951
					msock.socket = s;
					goto randomize;
P
Philipp Reisner 已提交
952
				}
953
				msock.socket = s;
P
Philipp Reisner 已提交
954 955
				break;
			default:
956
				conn_warn(connection, "Error receiving initial packet\n");
P
Philipp Reisner 已提交
957
				sock_release(s);
958
randomize:
959
				if (prandom_u32() & 1)
P
Philipp Reisner 已提交
960 961 962 963
					goto retry;
			}
		}

964
		if (connection->cstate <= C_DISCONNECTING)
P
Philipp Reisner 已提交
965 966 967 968
			goto out_release_sockets;
		if (signal_pending(current)) {
			flush_signals(current);
			smp_rmb();
969
			if (get_t_state(&connection->receiver) == EXITING)
P
Philipp Reisner 已提交
970 971 972
				goto out_release_sockets;
		}

973 974 975
		ok = drbd_socket_okay(&sock.socket);
		ok = drbd_socket_okay(&msock.socket) && ok;
	} while (!ok);
P
Philipp Reisner 已提交
976

977 978
	if (ad.s_listen)
		sock_release(ad.s_listen);
P
Philipp Reisner 已提交
979

980 981
	sock.socket->sk->sk_reuse = SK_CAN_REUSE; /* SO_REUSEADDR */
	msock.socket->sk->sk_reuse = SK_CAN_REUSE; /* SO_REUSEADDR */
P
Philipp Reisner 已提交
982

983 984
	sock.socket->sk->sk_allocation = GFP_NOIO;
	msock.socket->sk->sk_allocation = GFP_NOIO;
P
Philipp Reisner 已提交
985

986 987
	sock.socket->sk->sk_priority = TC_PRIO_INTERACTIVE_BULK;
	msock.socket->sk->sk_priority = TC_PRIO_INTERACTIVE;
P
Philipp Reisner 已提交
988 989

	/* NOT YET ...
990
	 * sock.socket->sk->sk_sndtimeo = connection->net_conf->timeout*HZ/10;
991
	 * sock.socket->sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
992
	 * first set it to the P_CONNECTION_FEATURES timeout,
P
Philipp Reisner 已提交
993
	 * which we set to 4x the configured ping_timeout. */
994
	rcu_read_lock();
995
	nc = rcu_dereference(connection->net_conf);
996

997 998
	sock.socket->sk->sk_sndtimeo =
	sock.socket->sk->sk_rcvtimeo = nc->ping_timeo*4*HZ/10;
P
Philipp Reisner 已提交
999

1000
	msock.socket->sk->sk_rcvtimeo = nc->ping_int*HZ;
1001
	timeout = nc->timeout * HZ / 10;
1002
	discard_my_data = nc->discard_my_data;
1003
	rcu_read_unlock();
P
Philipp Reisner 已提交
1004

1005
	msock.socket->sk->sk_sndtimeo = timeout;
P
Philipp Reisner 已提交
1006 1007

	/* we don't want delays.
L
Lucas De Marchi 已提交
1008
	 * we use TCP_CORK where appropriate, though */
1009 1010
	drbd_tcp_nodelay(sock.socket);
	drbd_tcp_nodelay(msock.socket);
P
Philipp Reisner 已提交
1011

1012 1013 1014
	connection->data.socket = sock.socket;
	connection->meta.socket = msock.socket;
	connection->last_received = jiffies;
P
Philipp Reisner 已提交
1015

1016
	h = drbd_do_features(connection);
P
Philipp Reisner 已提交
1017 1018 1019
	if (h <= 0)
		return h;

1020
	if (connection->cram_hmac_tfm) {
1021
		/* drbd_request_state(device, NS(conn, WFAuth)); */
1022
		switch (drbd_do_auth(connection)) {
1023
		case -1:
1024
			conn_err(connection, "Authentication of peer failed\n");
P
Philipp Reisner 已提交
1025
			return -1;
1026
		case 0:
1027
			conn_err(connection, "Authentication of peer failed, trying again.\n");
1028
			return 0;
P
Philipp Reisner 已提交
1029 1030 1031
		}
	}

1032 1033
	connection->data.socket->sk->sk_sndtimeo = timeout;
	connection->data.socket->sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT;
P
Philipp Reisner 已提交
1034

1035
	if (drbd_send_protocol(connection) == -EOPNOTSUPP)
1036
		return -1;
P
Philipp Reisner 已提交
1037

1038
	set_bit(STATE_SENT, &connection->flags);
1039

P
Philipp Reisner 已提交
1040
	rcu_read_lock();
1041
	idr_for_each_entry(&connection->volumes, device, vnr) {
1042
		kref_get(&device->kref);
1043 1044
		rcu_read_unlock();

1045 1046 1047 1048 1049 1050 1051
		/* 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.
		 */
1052 1053
		mutex_lock(device->state_mutex);
		mutex_unlock(device->state_mutex);
1054

1055
		if (discard_my_data)
1056
			set_bit(DISCARD_MY_DATA, &device->flags);
1057
		else
1058
			clear_bit(DISCARD_MY_DATA, &device->flags);
1059

1060 1061
		drbd_connected(device);
		kref_put(&device->kref, &drbd_minor_destroy);
P
Philipp Reisner 已提交
1062 1063 1064 1065
		rcu_read_lock();
	}
	rcu_read_unlock();

1066 1067 1068
	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);
1069
		return 0;
1070
	}
1071

1072
	drbd_thread_start(&connection->asender);
P
Philipp Reisner 已提交
1073

1074
	mutex_lock(&connection->conf_update);
1075 1076 1077 1078
	/* 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. */
1079 1080
	connection->net_conf->discard_my_data = 0;
	mutex_unlock(&connection->conf_update);
1081

1082
	return h;
P
Philipp Reisner 已提交
1083 1084

out_release_sockets:
1085 1086
	if (ad.s_listen)
		sock_release(ad.s_listen);
1087 1088 1089 1090
	if (sock.socket)
		sock_release(sock.socket);
	if (msock.socket)
		sock_release(msock.socket);
P
Philipp Reisner 已提交
1091 1092 1093
	return -1;
}

1094
static int decode_header(struct drbd_connection *connection, void *header, struct packet_info *pi)
P
Philipp Reisner 已提交
1095
{
1096
	unsigned int header_size = drbd_header_size(connection);
1097

1098 1099 1100 1101
	if (header_size == sizeof(struct p_header100) &&
	    *(__be32 *)header == cpu_to_be32(DRBD_MAGIC_100)) {
		struct p_header100 *h = header;
		if (h->pad != 0) {
1102
			conn_err(connection, "Header padding is not zero\n");
1103 1104 1105 1106 1107 1108 1109
			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)) {
1110 1111
		struct p_header95 *h = header;
		pi->cmd = be16_to_cpu(h->command);
1112 1113
		pi->size = be32_to_cpu(h->length);
		pi->vnr = 0;
1114 1115 1116 1117 1118
	} 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);
1119
		pi->vnr = 0;
1120
	} else {
1121
		conn_err(connection, "Wrong magic value 0x%08x in protocol version %d\n",
1122
			 be32_to_cpu(*(__be32 *)header),
1123
			 connection->agreed_pro_version);
1124
		return -EINVAL;
P
Philipp Reisner 已提交
1125
	}
1126
	pi->data = header + header_size;
1127
	return 0;
1128
}
P
Philipp Reisner 已提交
1129

1130
static int drbd_recv_header(struct drbd_connection *connection, struct packet_info *pi)
1131
{
1132
	void *buffer = connection->data.rbuf;
1133
	int err;
1134

1135
	err = drbd_recv_all_warn(connection, buffer, drbd_header_size(connection));
1136
	if (err)
1137
		return err;
1138

1139 1140
	err = decode_header(connection, buffer, pi);
	connection->last_received = jiffies;
P
Philipp Reisner 已提交
1141

1142
	return err;
P
Philipp Reisner 已提交
1143 1144
}

1145
static void drbd_flush(struct drbd_connection *connection)
P
Philipp Reisner 已提交
1146 1147
{
	int rv;
1148
	struct drbd_device *device;
1149 1150
	int vnr;

1151
	if (connection->write_ordering >= WO_bdev_flush) {
1152
		rcu_read_lock();
1153
		idr_for_each_entry(&connection->volumes, device, vnr) {
1154
			if (!get_ldev(device))
1155
				continue;
1156
			kref_get(&device->kref);
1157 1158
			rcu_read_unlock();

1159
			rv = blkdev_issue_flush(device->ldev->backing_bdev,
1160 1161 1162 1163 1164 1165
					GFP_NOIO, NULL);
			if (rv) {
				dev_info(DEV, "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) */
1166
				drbd_bump_write_ordering(connection, WO_drain_io);
1167
			}
1168 1169
			put_ldev(device);
			kref_put(&device->kref, &drbd_minor_destroy);
P
Philipp Reisner 已提交
1170

1171 1172 1173
			rcu_read_lock();
			if (rv)
				break;
P
Philipp Reisner 已提交
1174
		}
1175
		rcu_read_unlock();
P
Philipp Reisner 已提交
1176 1177 1178 1179 1180
	}
}

/**
 * drbd_may_finish_epoch() - Applies an epoch_event to the epoch's state, eventually finishes it.
1181
 * @device:	DRBD device.
P
Philipp Reisner 已提交
1182 1183 1184
 * @epoch:	Epoch object.
 * @ev:		Epoch event.
 */
1185
static enum finish_epoch drbd_may_finish_epoch(struct drbd_connection *connection,
P
Philipp Reisner 已提交
1186 1187 1188
					       struct drbd_epoch *epoch,
					       enum epoch_event ev)
{
1189
	int epoch_size;
P
Philipp Reisner 已提交
1190 1191 1192
	struct drbd_epoch *next_epoch;
	enum finish_epoch rv = FE_STILL_LIVE;

1193
	spin_lock(&connection->epoch_lock);
P
Philipp Reisner 已提交
1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212
	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 &&
1213
		    (test_bit(DE_HAVE_BARRIER_NUMBER, &epoch->flags) || ev & EV_CLEANUP)) {
P
Philipp Reisner 已提交
1214
			if (!(ev & EV_CLEANUP)) {
1215 1216 1217
				spin_unlock(&connection->epoch_lock);
				drbd_send_b_ack(epoch->connection, epoch->barrier_nr, epoch_size);
				spin_lock(&connection->epoch_lock);
P
Philipp Reisner 已提交
1218
			}
1219 1220 1221
#if 0
			/* FIXME: dec unacked on connection, once we have
			 * something to count pending connection packets in. */
1222
			if (test_bit(DE_HAVE_BARRIER_NUMBER, &epoch->flags))
1223
				dec_unacked(epoch->connection);
1224
#endif
P
Philipp Reisner 已提交
1225

1226
			if (connection->current_epoch != epoch) {
P
Philipp Reisner 已提交
1227 1228 1229
				next_epoch = list_entry(epoch->list.next, struct drbd_epoch, list);
				list_del(&epoch->list);
				ev = EV_BECAME_LAST | (ev & EV_CLEANUP);
1230
				connection->epochs--;
P
Philipp Reisner 已提交
1231 1232 1233 1234 1235 1236 1237
				kfree(epoch);

				if (rv == FE_STILL_LIVE)
					rv = FE_DESTROYED;
			} else {
				epoch->flags = 0;
				atomic_set(&epoch->epoch_size, 0);
1238
				/* atomic_set(&epoch->active, 0); is already zero */
P
Philipp Reisner 已提交
1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249
				if (rv == FE_STILL_LIVE)
					rv = FE_RECYCLED;
			}
		}

		if (!next_epoch)
			break;

		epoch = next_epoch;
	} while (1);

1250
	spin_unlock(&connection->epoch_lock);
P
Philipp Reisner 已提交
1251 1252 1253 1254 1255 1256

	return rv;
}

/**
 * drbd_bump_write_ordering() - Fall back to an other write ordering method
1257
 * @connection:	DRBD connection.
P
Philipp Reisner 已提交
1258 1259
 * @wo:		Write ordering method to try.
 */
1260
void drbd_bump_write_ordering(struct drbd_connection *connection, enum write_ordering_e wo)
P
Philipp Reisner 已提交
1261
{
P
Philipp Reisner 已提交
1262
	struct disk_conf *dc;
1263
	struct drbd_device *device;
P
Philipp Reisner 已提交
1264
	enum write_ordering_e pwo;
1265
	int vnr;
P
Philipp Reisner 已提交
1266 1267 1268 1269 1270 1271
	static char *write_ordering_str[] = {
		[WO_none] = "none",
		[WO_drain_io] = "drain",
		[WO_bdev_flush] = "flush",
	};

1272
	pwo = connection->write_ordering;
P
Philipp Reisner 已提交
1273
	wo = min(pwo, wo);
P
Philipp Reisner 已提交
1274
	rcu_read_lock();
1275
	idr_for_each_entry(&connection->volumes, device, vnr) {
1276
		if (!get_ldev_if_state(device, D_ATTACHING))
1277
			continue;
1278
		dc = rcu_dereference(device->ldev->disk_conf);
1279 1280 1281 1282 1283

		if (wo == WO_bdev_flush && !dc->disk_flushes)
			wo = WO_drain_io;
		if (wo == WO_drain_io && !dc->disk_drain)
			wo = WO_none;
1284
		put_ldev(device);
1285
	}
P
Philipp Reisner 已提交
1286
	rcu_read_unlock();
1287 1288 1289
	connection->write_ordering = wo;
	if (pwo != connection->write_ordering || wo == WO_bdev_flush)
		conn_info(connection, "Method to ensure write ordering: %s\n", write_ordering_str[connection->write_ordering]);
P
Philipp Reisner 已提交
1290 1291
}

1292
/**
1293
 * drbd_submit_peer_request()
1294
 * @device:	DRBD device.
1295
 * @peer_req:	peer request
1296
 * @rw:		flag field, see bio->bi_rw
1297 1298 1299 1300 1301 1302 1303 1304 1305 1306
 *
 * 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.
1307 1308
 */
/* TODO allocate from our own bio_set. */
1309
int drbd_submit_peer_request(struct drbd_device *device,
1310 1311
			     struct drbd_peer_request *peer_req,
			     const unsigned rw, const int fault_type)
1312 1313 1314
{
	struct bio *bios = NULL;
	struct bio *bio;
1315 1316 1317
	struct page *page = peer_req->pages;
	sector_t sector = peer_req->i.sector;
	unsigned ds = peer_req->i.size;
1318 1319
	unsigned n_bios = 0;
	unsigned nr_pages = (ds + PAGE_SIZE -1) >> PAGE_SHIFT;
1320
	int err = -ENOMEM;
1321 1322 1323 1324

	/* 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
1325 1326 1327 1328 1329
	 * 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.
	 */
1330 1331 1332 1333 1334 1335
next_bio:
	bio = bio_alloc(GFP_NOIO, nr_pages);
	if (!bio) {
		dev_err(DEV, "submit_ee: Allocation of a bio failed\n");
		goto fail;
	}
1336
	/* > peer_req->i.sector, unless this is the first bio */
1337
	bio->bi_iter.bi_sector = sector;
1338
	bio->bi_bdev = device->ldev->backing_bdev;
1339
	bio->bi_rw = rw;
1340
	bio->bi_private = peer_req;
1341
	bio->bi_end_io = drbd_peer_request_endio;
1342 1343 1344 1345 1346 1347 1348 1349

	bio->bi_next = bios;
	bios = bio;
	++n_bios;

	page_chain_for_each(page) {
		unsigned len = min_t(unsigned, ds, PAGE_SIZE);
		if (!bio_add_page(bio, page, len, 0)) {
1350 1351 1352 1353 1354 1355 1356
			/* 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) {
				dev_err(DEV,
					"bio_add_page failed for len=%u, "
					"bi_vcnt=0 (bi_sector=%llu)\n",
1357
					len, (uint64_t)bio->bi_iter.bi_sector);
1358 1359 1360
				err = -ENOSPC;
				goto fail;
			}
1361 1362 1363 1364 1365 1366 1367 1368 1369
			goto next_bio;
		}
		ds -= len;
		sector += len >> 9;
		--nr_pages;
	}
	D_ASSERT(page == NULL);
	D_ASSERT(ds == 0);

1370
	atomic_set(&peer_req->pending_bios, n_bios);
1371 1372 1373 1374 1375
	do {
		bio = bios;
		bios = bios->bi_next;
		bio->bi_next = NULL;

1376
		drbd_generic_make_request(device, fault_type, bio);
1377 1378 1379 1380 1381 1382 1383 1384 1385
	} while (bios);
	return 0;

fail:
	while (bios) {
		bio = bios;
		bios = bios->bi_next;
		bio_put(bio);
	}
1386
	return err;
1387 1388
}

1389
static void drbd_remove_epoch_entry_interval(struct drbd_device *device,
1390
					     struct drbd_peer_request *peer_req)
1391
{
1392
	struct drbd_interval *i = &peer_req->i;
1393

1394
	drbd_remove_interval(&device->write_requests, i);
1395 1396
	drbd_clear_interval(i);

A
Andreas Gruenbacher 已提交
1397
	/* Wake up any processes waiting for this peer request to complete.  */
1398
	if (i->waiting)
1399
		wake_up(&device->misc_wait);
1400 1401
}

1402
static void conn_wait_active_ee_empty(struct drbd_connection *connection)
1403
{
1404
	struct drbd_device *device;
1405 1406 1407
	int vnr;

	rcu_read_lock();
1408
	idr_for_each_entry(&connection->volumes, device, vnr) {
1409
		kref_get(&device->kref);
1410
		rcu_read_unlock();
1411 1412
		drbd_wait_ee_list_empty(device, &device->active_ee);
		kref_put(&device->kref, &drbd_minor_destroy);
1413 1414 1415 1416 1417
		rcu_read_lock();
	}
	rcu_read_unlock();
}

1418
static int receive_Barrier(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
1419
{
1420
	int rv;
1421
	struct p_barrier *p = pi->data;
P
Philipp Reisner 已提交
1422 1423
	struct drbd_epoch *epoch;

1424 1425 1426
	/* FIXME these are unacked on connection,
	 * not a specific (peer)device.
	 */
1427 1428 1429
	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
Philipp Reisner 已提交
1430 1431 1432 1433 1434 1435

	/* 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. */
1436
	switch (connection->write_ordering) {
P
Philipp Reisner 已提交
1437 1438
	case WO_none:
		if (rv == FE_RECYCLED)
1439
			return 0;
1440 1441 1442 1443 1444 1445 1446

		/* 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
1447
			conn_warn(connection, "Allocation of an epoch failed, slowing down\n");
1448
			/* Fall through */
P
Philipp Reisner 已提交
1449 1450 1451

	case WO_bdev_flush:
	case WO_drain_io:
1452 1453
		conn_wait_active_ee_empty(connection);
		drbd_flush(connection);
1454

1455
		if (atomic_read(&connection->current_epoch->epoch_size)) {
1456 1457 1458
			epoch = kmalloc(sizeof(struct drbd_epoch), GFP_NOIO);
			if (epoch)
				break;
P
Philipp Reisner 已提交
1459 1460
		}

1461
		return 0;
1462
	default:
1463
		conn_err(connection, "Strangeness in connection->write_ordering %d\n", connection->write_ordering);
1464
		return -EIO;
P
Philipp Reisner 已提交
1465 1466 1467 1468 1469 1470
	}

	epoch->flags = 0;
	atomic_set(&epoch->epoch_size, 0);
	atomic_set(&epoch->active, 0);

1471 1472 1473 1474 1475
	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++;
P
Philipp Reisner 已提交
1476 1477 1478 1479
	} else {
		/* The current_epoch got recycled while we allocated this one... */
		kfree(epoch);
	}
1480
	spin_unlock(&connection->epoch_lock);
P
Philipp Reisner 已提交
1481

1482
	return 0;
P
Philipp Reisner 已提交
1483 1484 1485 1486
}

/* used from receive_RSDataReply (recv_resync_read)
 * and from receive_Data */
1487
static struct drbd_peer_request *
1488
read_in_block(struct drbd_device *device, u64 id, sector_t sector,
1489
	      int data_size) __must_hold(local)
P
Philipp Reisner 已提交
1490
{
1491
	const sector_t capacity = drbd_get_capacity(device->this_bdev);
1492
	struct drbd_peer_request *peer_req;
P
Philipp Reisner 已提交
1493
	struct page *page;
1494
	int dgs, ds, err;
1495 1496
	void *dig_in = device->connection->int_dig_in;
	void *dig_vv = device->connection->int_dig_vv;
1497
	unsigned long *data;
P
Philipp Reisner 已提交
1498

1499
	dgs = 0;
1500 1501
	if (device->connection->peer_integrity_tfm) {
		dgs = crypto_hash_digestsize(device->connection->peer_integrity_tfm);
1502 1503 1504 1505
		/*
		 * FIXME: Receive the incoming digest into the receive buffer
		 *	  here, together with its struct p_data?
		 */
1506
		err = drbd_recv_all_warn(device->connection, dig_in, dgs);
1507
		if (err)
P
Philipp Reisner 已提交
1508
			return NULL;
1509
		data_size -= dgs;
P
Philipp Reisner 已提交
1510 1511
	}

1512 1513 1514 1515
	if (!expect(IS_ALIGNED(data_size, 512)))
		return NULL;
	if (!expect(data_size <= DRBD_MAX_BIO_SIZE))
		return NULL;
P
Philipp Reisner 已提交
1516

1517 1518 1519
	/* even though we trust out peer,
	 * we sometimes have to double check. */
	if (sector + (data_size>>9) > capacity) {
1520 1521
		dev_err(DEV, "request from peer beyond end of local disk: "
			"capacity: %llus < sector: %llus + size: %u\n",
1522 1523 1524 1525 1526
			(unsigned long long)capacity,
			(unsigned long long)sector, data_size);
		return NULL;
	}

P
Philipp Reisner 已提交
1527 1528 1529
	/* 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.  */
1530
	peer_req = drbd_alloc_peer_req(device, id, sector, data_size, GFP_NOIO);
1531
	if (!peer_req)
P
Philipp Reisner 已提交
1532
		return NULL;
1533

1534
	if (!data_size)
1535
		return peer_req;
1536

P
Philipp Reisner 已提交
1537
	ds = data_size;
1538
	page = peer_req->pages;
1539 1540
	page_chain_for_each(page) {
		unsigned len = min_t(int, ds, PAGE_SIZE);
1541
		data = kmap(page);
1542
		err = drbd_recv_all_warn(device->connection, data, len);
1543
		if (drbd_insert_fault(device, DRBD_FAULT_RECEIVE)) {
1544 1545 1546
			dev_err(DEV, "Fault injection: Corrupting data on receive\n");
			data[0] = data[0] ^ (unsigned long)-1;
		}
P
Philipp Reisner 已提交
1547
		kunmap(page);
1548
		if (err) {
1549
			drbd_free_peer_req(device, peer_req);
P
Philipp Reisner 已提交
1550 1551
			return NULL;
		}
1552
		ds -= len;
P
Philipp Reisner 已提交
1553 1554 1555
	}

	if (dgs) {
1556
		drbd_csum_ee(device, device->connection->peer_integrity_tfm, peer_req, dig_vv);
P
Philipp Reisner 已提交
1557
		if (memcmp(dig_in, dig_vv, dgs)) {
1558 1559
			dev_err(DEV, "Digest integrity check FAILED: %llus +%u\n",
				(unsigned long long)sector, data_size);
1560
			drbd_free_peer_req(device, peer_req);
P
Philipp Reisner 已提交
1561 1562 1563
			return NULL;
		}
	}
1564
	device->recv_cnt += data_size>>9;
1565
	return peer_req;
P
Philipp Reisner 已提交
1566 1567 1568 1569 1570
}

/* drbd_drain_block() just takes a data block
 * out of the socket input buffer, and discards it.
 */
1571
static int drbd_drain_block(struct drbd_device *device, int data_size)
P
Philipp Reisner 已提交
1572 1573
{
	struct page *page;
1574
	int err = 0;
P
Philipp Reisner 已提交
1575 1576
	void *data;

1577
	if (!data_size)
1578
		return 0;
1579

1580
	page = drbd_alloc_pages(device, 1, 1);
P
Philipp Reisner 已提交
1581 1582 1583

	data = kmap(page);
	while (data_size) {
1584 1585
		unsigned int len = min_t(int, data_size, PAGE_SIZE);

1586
		err = drbd_recv_all_warn(device->connection, data, len);
1587
		if (err)
P
Philipp Reisner 已提交
1588
			break;
1589
		data_size -= len;
P
Philipp Reisner 已提交
1590 1591
	}
	kunmap(page);
1592
	drbd_free_pages(device, page, 0);
1593
	return err;
P
Philipp Reisner 已提交
1594 1595
}

1596
static int recv_dless_read(struct drbd_device *device, struct drbd_request *req,
P
Philipp Reisner 已提交
1597 1598
			   sector_t sector, int data_size)
{
1599 1600
	struct bio_vec bvec;
	struct bvec_iter iter;
P
Philipp Reisner 已提交
1601
	struct bio *bio;
1602
	int dgs, err, expect;
1603 1604
	void *dig_in = device->connection->int_dig_in;
	void *dig_vv = device->connection->int_dig_vv;
P
Philipp Reisner 已提交
1605

1606
	dgs = 0;
1607 1608 1609
	if (device->connection->peer_integrity_tfm) {
		dgs = crypto_hash_digestsize(device->connection->peer_integrity_tfm);
		err = drbd_recv_all_warn(device->connection, dig_in, dgs);
1610 1611
		if (err)
			return err;
1612
		data_size -= dgs;
P
Philipp Reisner 已提交
1613 1614 1615 1616
	}

	/* optimistically update recv_cnt.  if receiving fails below,
	 * we disconnect anyways, and counters will be reset. */
1617
	device->recv_cnt += data_size>>9;
P
Philipp Reisner 已提交
1618 1619

	bio = req->master_bio;
1620
	D_ASSERT(sector == bio->bi_iter.bi_sector);
P
Philipp Reisner 已提交
1621

1622 1623 1624
	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);
1625
		err = drbd_recv_all_warn(device->connection, mapped, expect);
1626
		kunmap(bvec.bv_page);
1627 1628 1629
		if (err)
			return err;
		data_size -= expect;
P
Philipp Reisner 已提交
1630 1631 1632
	}

	if (dgs) {
1633
		drbd_csum_bio(device, device->connection->peer_integrity_tfm, bio, dig_vv);
P
Philipp Reisner 已提交
1634 1635
		if (memcmp(dig_in, dig_vv, dgs)) {
			dev_err(DEV, "Digest integrity check FAILED. Broken NICs?\n");
1636
			return -EINVAL;
P
Philipp Reisner 已提交
1637 1638 1639 1640
		}
	}

	D_ASSERT(data_size == 0);
1641
	return 0;
P
Philipp Reisner 已提交
1642 1643
}

1644 1645 1646 1647
/*
 * e_end_resync_block() is called in asender context via
 * drbd_finish_peer_reqs().
 */
1648
static int e_end_resync_block(struct drbd_work *w, int unused)
P
Philipp Reisner 已提交
1649
{
1650 1651
	struct drbd_peer_request *peer_req =
		container_of(w, struct drbd_peer_request, w);
1652
	struct drbd_device *device = w->device;
1653
	sector_t sector = peer_req->i.sector;
1654
	int err;
P
Philipp Reisner 已提交
1655

1656
	D_ASSERT(drbd_interval_empty(&peer_req->i));
P
Philipp Reisner 已提交
1657

1658
	if (likely((peer_req->flags & EE_WAS_ERROR) == 0)) {
1659 1660
		drbd_set_in_sync(device, sector, peer_req->i.size);
		err = drbd_send_ack(device, P_RS_WRITE_ACK, peer_req);
P
Philipp Reisner 已提交
1661 1662
	} else {
		/* Record failure to sync */
1663
		drbd_rs_failed_io(device, sector, peer_req->i.size);
P
Philipp Reisner 已提交
1664

1665
		err  = drbd_send_ack(device, P_NEG_ACK, peer_req);
P
Philipp Reisner 已提交
1666
	}
1667
	dec_unacked(device);
P
Philipp Reisner 已提交
1668

1669
	return err;
P
Philipp Reisner 已提交
1670 1671
}

1672
static int recv_resync_read(struct drbd_device *device, sector_t sector, int data_size) __releases(local)
P
Philipp Reisner 已提交
1673
{
1674
	struct drbd_peer_request *peer_req;
P
Philipp Reisner 已提交
1675

1676
	peer_req = read_in_block(device, ID_SYNCER, sector, data_size);
1677
	if (!peer_req)
1678
		goto fail;
P
Philipp Reisner 已提交
1679

1680
	dec_rs_pending(device);
P
Philipp Reisner 已提交
1681

1682
	inc_unacked(device);
P
Philipp Reisner 已提交
1683 1684 1685
	/* corresponding dec_unacked() in e_end_resync_block()
	 * respective _drbd_clear_done_ee */

1686
	peer_req->w.cb = e_end_resync_block;
1687

1688
	spin_lock_irq(&device->connection->req_lock);
1689
	list_add(&peer_req->w.list, &device->sync_ee);
1690
	spin_unlock_irq(&device->connection->req_lock);
P
Philipp Reisner 已提交
1691

1692 1693
	atomic_add(data_size >> 9, &device->rs_sect_ev);
	if (drbd_submit_peer_request(device, peer_req, WRITE, DRBD_FAULT_RS_WR) == 0)
1694
		return 0;
P
Philipp Reisner 已提交
1695

1696 1697
	/* don't care for the reason here */
	dev_err(DEV, "submit failed, triggering re-connect\n");
1698
	spin_lock_irq(&device->connection->req_lock);
1699
	list_del(&peer_req->w.list);
1700
	spin_unlock_irq(&device->connection->req_lock);
1701

1702
	drbd_free_peer_req(device, peer_req);
1703
fail:
1704
	put_ldev(device);
1705
	return -EIO;
P
Philipp Reisner 已提交
1706 1707
}

1708
static struct drbd_request *
1709
find_request(struct drbd_device *device, struct rb_root *root, u64 id,
1710
	     sector_t sector, bool missing_ok, const char *func)
1711 1712 1713
{
	struct drbd_request *req;

1714 1715
	/* Request object according to our peer */
	req = (struct drbd_request *)(unsigned long)id;
1716
	if (drbd_contains_interval(root, sector, &req->i) && req->i.local)
1717
		return req;
1718
	if (!missing_ok) {
1719
		dev_err(DEV, "%s: failed to find request 0x%lx, sector %llus\n", func,
1720 1721
			(unsigned long)id, (unsigned long long)sector);
	}
1722
	return NULL;
P
Philipp Reisner 已提交
1723 1724
}

1725
static int receive_DataReply(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
1726
{
1727
	struct drbd_device *device;
P
Philipp Reisner 已提交
1728 1729
	struct drbd_request *req;
	sector_t sector;
1730
	int err;
1731
	struct p_data *p = pi->data;
1732

1733
	device = vnr_to_device(connection, pi->vnr);
1734
	if (!device)
1735
		return -EIO;
P
Philipp Reisner 已提交
1736 1737 1738

	sector = be64_to_cpu(p->sector);

1739
	spin_lock_irq(&device->connection->req_lock);
1740
	req = find_request(device, &device->read_requests, p->block_id, sector, false, __func__);
1741
	spin_unlock_irq(&device->connection->req_lock);
1742
	if (unlikely(!req))
1743
		return -EIO;
P
Philipp Reisner 已提交
1744

B
Bart Van Assche 已提交
1745
	/* hlist_del(&req->collision) is done in _req_may_be_done, to avoid
P
Philipp Reisner 已提交
1746 1747
	 * special casing it there for the various failure cases.
	 * still no race with drbd_fail_pending_reads */
1748
	err = recv_dless_read(device, req, sector, pi->size);
1749
	if (!err)
1750
		req_mod(req, DATA_RECEIVED);
P
Philipp Reisner 已提交
1751 1752 1753 1754
	/* else: nothing. handled from drbd_disconnect...
	 * I don't think we may complete this just yet
	 * in case we are "on-disconnect: freeze" */

1755
	return err;
P
Philipp Reisner 已提交
1756 1757
}

1758
static int receive_RSDataReply(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
1759
{
1760
	struct drbd_device *device;
P
Philipp Reisner 已提交
1761
	sector_t sector;
1762
	int err;
1763
	struct p_data *p = pi->data;
1764

1765
	device = vnr_to_device(connection, pi->vnr);
1766
	if (!device)
1767
		return -EIO;
P
Philipp Reisner 已提交
1768 1769 1770 1771

	sector = be64_to_cpu(p->sector);
	D_ASSERT(p->block_id == ID_SYNCER);

1772
	if (get_ldev(device)) {
P
Philipp Reisner 已提交
1773 1774
		/* data is submitted to disk within recv_resync_read.
		 * corresponding put_ldev done below on error,
1775
		 * or in drbd_peer_request_endio. */
1776
		err = recv_resync_read(device, sector, pi->size);
P
Philipp Reisner 已提交
1777 1778 1779 1780
	} else {
		if (__ratelimit(&drbd_ratelimit_state))
			dev_err(DEV, "Can not write resync data to local disk.\n");

1781
		err = drbd_drain_block(device, pi->size);
P
Philipp Reisner 已提交
1782

1783
		drbd_send_ack_dp(device, P_NEG_ACK, p, pi->size);
P
Philipp Reisner 已提交
1784 1785
	}

1786
	atomic_add(pi->size >> 9, &device->rs_sect_in);
1787

1788
	return err;
P
Philipp Reisner 已提交
1789 1790
}

1791
static void restart_conflicting_writes(struct drbd_device *device,
1792
				       sector_t sector, int size)
P
Philipp Reisner 已提交
1793
{
1794 1795 1796
	struct drbd_interval *i;
	struct drbd_request *req;

1797
	drbd_for_each_overlap(i, &device->write_requests, sector, size) {
1798 1799 1800 1801 1802 1803
		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;
1804 1805
		/* as it is RQ_POSTPONED, this will cause it to
		 * be queued on the retry workqueue. */
1806
		__req_mod(req, CONFLICT_RESOLVED, NULL);
1807 1808
	}
}
P
Philipp Reisner 已提交
1809

1810 1811
/*
 * e_end_block() is called in asender context via drbd_finish_peer_reqs().
P
Philipp Reisner 已提交
1812
 */
1813
static int e_end_block(struct drbd_work *w, int cancel)
P
Philipp Reisner 已提交
1814
{
1815 1816
	struct drbd_peer_request *peer_req =
		container_of(w, struct drbd_peer_request, w);
1817
	struct drbd_device *device = w->device;
1818
	sector_t sector = peer_req->i.sector;
1819
	int err = 0, pcmd;
P
Philipp Reisner 已提交
1820

1821
	if (peer_req->flags & EE_SEND_WRITE_ACK) {
1822
		if (likely((peer_req->flags & EE_WAS_ERROR) == 0)) {
1823 1824
			pcmd = (device->state.conn >= C_SYNC_SOURCE &&
				device->state.conn <= C_PAUSED_SYNC_T &&
1825
				peer_req->flags & EE_MAY_SET_IN_SYNC) ?
P
Philipp Reisner 已提交
1826
				P_RS_WRITE_ACK : P_WRITE_ACK;
1827
			err = drbd_send_ack(device, pcmd, peer_req);
P
Philipp Reisner 已提交
1828
			if (pcmd == P_RS_WRITE_ACK)
1829
				drbd_set_in_sync(device, sector, peer_req->i.size);
P
Philipp Reisner 已提交
1830
		} else {
1831
			err = drbd_send_ack(device, P_NEG_ACK, peer_req);
P
Philipp Reisner 已提交
1832 1833 1834
			/* we expect it to be marked out of sync anyways...
			 * maybe assert this?  */
		}
1835
		dec_unacked(device);
P
Philipp Reisner 已提交
1836 1837 1838
	}
	/* we delete from the conflict detection hash _after_ we sent out the
	 * P_WRITE_ACK / P_NEG_ACK, to get the sequence number right.  */
1839
	if (peer_req->flags & EE_IN_INTERVAL_TREE) {
1840
		spin_lock_irq(&device->connection->req_lock);
1841
		D_ASSERT(!drbd_interval_empty(&peer_req->i));
1842
		drbd_remove_epoch_entry_interval(device, peer_req);
1843
		if (peer_req->flags & EE_RESTART_REQUESTS)
1844
			restart_conflicting_writes(device, sector, peer_req->i.size);
1845
		spin_unlock_irq(&device->connection->req_lock);
1846
	} else
1847
		D_ASSERT(drbd_interval_empty(&peer_req->i));
P
Philipp Reisner 已提交
1848

1849
	drbd_may_finish_epoch(device->connection, peer_req->epoch, EV_PUT + (cancel ? EV_CLEANUP : 0));
P
Philipp Reisner 已提交
1850

1851
	return err;
P
Philipp Reisner 已提交
1852 1853
}

1854
static int e_send_ack(struct drbd_work *w, enum drbd_packet ack)
P
Philipp Reisner 已提交
1855
{
1856
	struct drbd_device *device = w->device;
1857 1858
	struct drbd_peer_request *peer_req =
		container_of(w, struct drbd_peer_request, w);
1859
	int err;
P
Philipp Reisner 已提交
1860

1861 1862
	err = drbd_send_ack(device, ack, peer_req);
	dec_unacked(device);
P
Philipp Reisner 已提交
1863

1864
	return err;
P
Philipp Reisner 已提交
1865 1866
}

1867
static int e_send_superseded(struct drbd_work *w, int unused)
1868
{
1869
	return e_send_ack(w, P_SUPERSEDED);
1870 1871
}

1872
static int e_send_retry_write(struct drbd_work *w, int unused)
1873
{
1874
	struct drbd_connection *connection = w->device->connection;
1875

1876
	return e_send_ack(w, connection->agreed_pro_version >= 100 ?
1877
			     P_RETRY_WRITE : P_SUPERSEDED);
1878
}
P
Philipp Reisner 已提交
1879

1880 1881 1882 1883 1884 1885 1886 1887 1888
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;
}
P
Philipp Reisner 已提交
1889

1890 1891 1892
static u32 seq_max(u32 a, u32 b)
{
	return seq_greater(a, b) ? a : b;
P
Philipp Reisner 已提交
1893 1894
}

1895
static void update_peer_seq(struct drbd_device *device, unsigned int peer_seq)
1896
{
1897
	unsigned int newest_peer_seq;
1898

1899
	if (test_bit(RESOLVE_CONFLICTS, &device->connection->flags)) {
1900 1901 1902 1903 1904
		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 */
1905
		if (peer_seq == newest_peer_seq)
1906
			wake_up(&device->seq_wait);
1907
	}
P
Philipp Reisner 已提交
1908 1909
}

1910
static inline int overlaps(sector_t s1, int l1, sector_t s2, int l2)
1911
{
1912 1913
	return !((s1 + (l1>>9) <= s2) || (s1 >= s2 + (l2>>9)));
}
1914

1915
/* maybe change sync_ee into interval trees as well? */
1916
static bool overlapping_resync_write(struct drbd_device *device, struct drbd_peer_request *peer_req)
1917 1918
{
	struct drbd_peer_request *rs_req;
1919 1920
	bool rv = 0;

1921
	spin_lock_irq(&device->connection->req_lock);
1922
	list_for_each_entry(rs_req, &device->sync_ee, w.list) {
1923 1924
		if (overlaps(peer_req->i.sector, peer_req->i.size,
			     rs_req->i.sector, rs_req->i.size)) {
1925 1926 1927 1928
			rv = 1;
			break;
		}
	}
1929
	spin_unlock_irq(&device->connection->req_lock);
1930 1931 1932 1933

	return rv;
}

P
Philipp Reisner 已提交
1934 1935 1936 1937 1938 1939 1940 1941 1942
/* 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.
 *
1943
 * In case packet_seq is larger than device->peer_seq number, there are
P
Philipp Reisner 已提交
1944
 * outstanding packets on the msock. We wait for them to arrive.
1945
 * In case we are the logically next packet, we update device->peer_seq
P
Philipp Reisner 已提交
1946 1947 1948 1949 1950 1951 1952 1953 1954
 * 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). */
1955
static int wait_for_and_update_peer_seq(struct drbd_device *device, const u32 peer_seq)
P
Philipp Reisner 已提交
1956 1957 1958
{
	DEFINE_WAIT(wait);
	long timeout;
1959
	int ret = 0, tp;
1960

1961
	if (!test_bit(RESOLVE_CONFLICTS, &device->connection->flags))
1962 1963
		return 0;

1964
	spin_lock(&device->peer_seq_lock);
P
Philipp Reisner 已提交
1965
	for (;;) {
1966 1967
		if (!seq_greater(peer_seq - 1, device->peer_seq)) {
			device->peer_seq = seq_max(device->peer_seq, peer_seq);
P
Philipp Reisner 已提交
1968
			break;
1969
		}
1970

P
Philipp Reisner 已提交
1971 1972 1973 1974
		if (signal_pending(current)) {
			ret = -ERESTARTSYS;
			break;
		}
1975 1976

		rcu_read_lock();
1977
		tp = rcu_dereference(device->connection->net_conf)->two_primaries;
1978 1979 1980 1981 1982 1983
		rcu_read_unlock();

		if (!tp)
			break;

		/* Only need to wait if two_primaries is enabled */
1984 1985
		prepare_to_wait(&device->seq_wait, &wait, TASK_INTERRUPTIBLE);
		spin_unlock(&device->peer_seq_lock);
1986
		rcu_read_lock();
1987
		timeout = rcu_dereference(device->connection->net_conf)->ping_timeo*HZ/10;
1988
		rcu_read_unlock();
1989
		timeout = schedule_timeout(timeout);
1990
		spin_lock(&device->peer_seq_lock);
1991
		if (!timeout) {
P
Philipp Reisner 已提交
1992
			ret = -ETIMEDOUT;
1993
			dev_err(DEV, "Timed out waiting for missing ack packets; disconnecting\n");
P
Philipp Reisner 已提交
1994 1995 1996
			break;
		}
	}
1997 1998
	spin_unlock(&device->peer_seq_lock);
	finish_wait(&device->seq_wait, &wait);
P
Philipp Reisner 已提交
1999 2000 2001
	return ret;
}

2002 2003 2004
/* 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. */
2005
static unsigned long wire_flags_to_bio(struct drbd_device *device, u32 dpf)
2006
{
2007 2008 2009 2010
	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);
2011 2012
}

2013
static void fail_postponed_requests(struct drbd_device *device, sector_t sector,
2014 2015 2016 2017 2018
				    unsigned int size)
{
	struct drbd_interval *i;

    repeat:
2019
	drbd_for_each_overlap(i, &device->write_requests, sector, size) {
2020 2021 2022 2023 2024 2025 2026 2027 2028 2029
		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);
2030
		spin_unlock_irq(&device->connection->req_lock);
2031
		if (m.bio)
2032
			complete_master_bio(device, &m);
2033
		spin_lock_irq(&device->connection->req_lock);
2034 2035 2036 2037
		goto repeat;
	}
}

2038
static int handle_write_conflicts(struct drbd_device *device,
2039 2040
				  struct drbd_peer_request *peer_req)
{
2041 2042
	struct drbd_connection *connection = device->connection;
	bool resolve_conflicts = test_bit(RESOLVE_CONFLICTS, &connection->flags);
2043 2044 2045 2046 2047 2048 2049 2050 2051 2052
	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.
	 */
2053
	drbd_insert_interval(&device->write_requests, &peer_req->i);
2054 2055

    repeat:
2056
	drbd_for_each_overlap(i, &device->write_requests, sector, size) {
2057 2058 2059 2060 2061 2062 2063 2064 2065
		if (i == &peer_req->i)
			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.
			 */
2066
			err = drbd_wait_misc(device, i);
2067 2068 2069 2070 2071 2072 2073 2074 2075
			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
2076 2077 2078
			 * overlapping request, it can be considered overwritten
			 * and thus superseded; otherwise, it will be retried
			 * once all overlapping requests have completed.
2079
			 */
2080
			bool superseded = i->sector <= sector && i->sector +
2081 2082 2083 2084 2085 2086 2087 2088
				       (i->size >> 9) >= sector + (size >> 9);

			if (!equal)
				dev_alert(DEV, "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,
2089
					  superseded ? "local" : "remote");
2090

2091
			inc_unacked(device);
2092
			peer_req->w.cb = superseded ? e_send_superseded :
2093
						   e_send_retry_write;
2094
			list_add_tail(&peer_req->w.list, &device->done_ee);
2095
			wake_asender(device->connection);
2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112

			err = -ENOENT;
			goto out;
		} else {
			struct drbd_request *req =
				container_of(i, struct drbd_request, i);

			if (!equal)
				dev_alert(DEV, "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
2113 2114 2115
				 * decide if this request has been superseded
				 * or needs to be retried.
				 * Requests that have been superseded will
2116 2117 2118 2119 2120 2121
				 * disappear from the write_requests tree.
				 *
				 * In addition, wait for the conflicting
				 * request to finish locally before submitting
				 * the conflicting peer request.
				 */
2122
				err = drbd_wait_misc(device, &req->i);
2123
				if (err) {
2124
					_conn_request_state(device->connection,
2125 2126
							    NS(conn, C_TIMEOUT),
							    CS_HARD);
2127
					fail_postponed_requests(device, sector, size);
2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142
					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)
2143
		drbd_remove_epoch_entry_interval(device, peer_req);
2144 2145 2146
	return err;
}

P
Philipp Reisner 已提交
2147
/* mirrored write */
2148
static int receive_Data(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
2149
{
2150
	struct drbd_device *device;
P
Philipp Reisner 已提交
2151
	sector_t sector;
2152
	struct drbd_peer_request *peer_req;
2153
	struct p_data *p = pi->data;
2154
	u32 peer_seq = be32_to_cpu(p->seq_num);
P
Philipp Reisner 已提交
2155 2156
	int rw = WRITE;
	u32 dp_flags;
2157
	int err, tp;
P
Philipp Reisner 已提交
2158

2159
	device = vnr_to_device(connection, pi->vnr);
2160
	if (!device)
2161
		return -EIO;
P
Philipp Reisner 已提交
2162

2163
	if (!get_ldev(device)) {
2164 2165
		int err2;

2166 2167
		err = wait_for_and_update_peer_seq(device, peer_seq);
		drbd_send_ack_dp(device, P_NEG_ACK, p, pi->size);
2168
		atomic_inc(&connection->current_epoch->epoch_size);
2169
		err2 = drbd_drain_block(device, pi->size);
2170 2171 2172
		if (!err)
			err = err2;
		return err;
P
Philipp Reisner 已提交
2173 2174
	}

2175 2176 2177 2178 2179
	/*
	 * 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.
	 */
P
Philipp Reisner 已提交
2180 2181

	sector = be64_to_cpu(p->sector);
2182
	peer_req = read_in_block(device, p->block_id, sector, pi->size);
2183
	if (!peer_req) {
2184
		put_ldev(device);
2185
		return -EIO;
P
Philipp Reisner 已提交
2186 2187
	}

2188
	peer_req->w.cb = e_end_block;
P
Philipp Reisner 已提交
2189

2190
	dp_flags = be32_to_cpu(p->dp_flags);
2191
	rw |= wire_flags_to_bio(device, dp_flags);
2192 2193
	if (peer_req->pages == NULL) {
		D_ASSERT(peer_req->i.size == 0);
2194 2195
		D_ASSERT(dp_flags & DP_FLUSH);
	}
2196 2197

	if (dp_flags & DP_MAY_SET_IN_SYNC)
2198
		peer_req->flags |= EE_MAY_SET_IN_SYNC;
2199

2200 2201
	spin_lock(&connection->epoch_lock);
	peer_req->epoch = connection->current_epoch;
2202 2203
	atomic_inc(&peer_req->epoch->epoch_size);
	atomic_inc(&peer_req->epoch->active);
2204
	spin_unlock(&connection->epoch_lock);
P
Philipp Reisner 已提交
2205

2206
	rcu_read_lock();
2207
	tp = rcu_dereference(device->connection->net_conf)->two_primaries;
2208 2209 2210
	rcu_read_unlock();
	if (tp) {
		peer_req->flags |= EE_IN_INTERVAL_TREE;
2211
		err = wait_for_and_update_peer_seq(device, peer_seq);
2212
		if (err)
P
Philipp Reisner 已提交
2213
			goto out_interrupted;
2214
		spin_lock_irq(&device->connection->req_lock);
2215
		err = handle_write_conflicts(device, peer_req);
2216
		if (err) {
2217
			spin_unlock_irq(&device->connection->req_lock);
2218
			if (err == -ENOENT) {
2219
				put_ldev(device);
2220
				return 0;
P
Philipp Reisner 已提交
2221
			}
2222
			goto out_interrupted;
P
Philipp Reisner 已提交
2223
		}
2224
	} else {
2225
		update_peer_seq(device, peer_seq);
2226
		spin_lock_irq(&device->connection->req_lock);
2227
	}
2228
	list_add(&peer_req->w.list, &device->active_ee);
2229
	spin_unlock_irq(&device->connection->req_lock);
P
Philipp Reisner 已提交
2230

2231 2232
	if (device->state.conn == C_SYNC_TARGET)
		wait_event(device->ee_wait, !overlapping_resync_write(device, peer_req));
P
Philipp Reisner 已提交
2233

2234
	if (device->connection->agreed_pro_version < 100) {
2235
		rcu_read_lock();
2236
		switch (rcu_dereference(device->connection->net_conf)->wire_protocol) {
2237 2238 2239 2240 2241 2242
		case DRBD_PROT_C:
			dp_flags |= DP_SEND_WRITE_ACK;
			break;
		case DRBD_PROT_B:
			dp_flags |= DP_SEND_RECEIVE_ACK;
			break;
P
Philipp Reisner 已提交
2243
		}
2244
		rcu_read_unlock();
P
Philipp Reisner 已提交
2245 2246
	}

2247 2248
	if (dp_flags & DP_SEND_WRITE_ACK) {
		peer_req->flags |= EE_SEND_WRITE_ACK;
2249
		inc_unacked(device);
P
Philipp Reisner 已提交
2250 2251
		/* corresponding dec_unacked() in e_end_block()
		 * respective _drbd_clear_done_ee */
2252 2253 2254
	}

	if (dp_flags & DP_SEND_RECEIVE_ACK) {
P
Philipp Reisner 已提交
2255 2256
		/* I really don't like it that the receiver thread
		 * sends on the msock, but anyways */
2257
		drbd_send_ack(device, P_RECV_ACK, peer_req);
P
Philipp Reisner 已提交
2258 2259
	}

2260
	if (device->state.pdsk < D_INCONSISTENT) {
P
Philipp Reisner 已提交
2261
		/* In case we have the only disk of the cluster, */
2262
		drbd_set_out_of_sync(device, peer_req->i.sector, peer_req->i.size);
2263 2264
		peer_req->flags |= EE_CALL_AL_COMPLETE_IO;
		peer_req->flags &= ~EE_MAY_SET_IN_SYNC;
2265
		drbd_al_begin_io(device, &peer_req->i, true);
P
Philipp Reisner 已提交
2266 2267
	}

2268
	err = drbd_submit_peer_request(device, peer_req, rw, DRBD_FAULT_DT_WR);
2269 2270
	if (!err)
		return 0;
P
Philipp Reisner 已提交
2271

2272 2273
	/* don't care for the reason here */
	dev_err(DEV, "submit failed, triggering re-connect\n");
2274
	spin_lock_irq(&device->connection->req_lock);
2275
	list_del(&peer_req->w.list);
2276
	drbd_remove_epoch_entry_interval(device, peer_req);
2277
	spin_unlock_irq(&device->connection->req_lock);
2278
	if (peer_req->flags & EE_CALL_AL_COMPLETE_IO)
2279
		drbd_al_complete_io(device, &peer_req->i);
2280

P
Philipp Reisner 已提交
2281
out_interrupted:
2282
	drbd_may_finish_epoch(connection, peer_req->epoch, EV_PUT + EV_CLEANUP);
2283 2284
	put_ldev(device);
	drbd_free_peer_req(device, peer_req);
2285
	return err;
P
Philipp Reisner 已提交
2286 2287
}

2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298
/* 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.
 */
2299
int drbd_rs_should_slow_down(struct drbd_device *device, sector_t sector)
2300
{
2301
	struct gendisk *disk = device->ldev->backing_bdev->bd_contains->bd_disk;
2302
	unsigned long db, dt, dbdt;
2303
	struct lc_element *tmp;
2304 2305
	int curr_events;
	int throttle = 0;
P
Philipp Reisner 已提交
2306 2307 2308
	unsigned int c_min_rate;

	rcu_read_lock();
2309
	c_min_rate = rcu_dereference(device->ldev->disk_conf)->c_min_rate;
P
Philipp Reisner 已提交
2310
	rcu_read_unlock();
2311 2312

	/* feature disabled? */
P
Philipp Reisner 已提交
2313
	if (c_min_rate == 0)
2314 2315
		return 0;

2316 2317
	spin_lock_irq(&device->al_lock);
	tmp = lc_find(device->resync, BM_SECT_TO_EXT(sector));
2318 2319 2320
	if (tmp) {
		struct bm_extent *bm_ext = lc_entry(tmp, struct bm_extent, lce);
		if (test_bit(BME_PRIORITY, &bm_ext->flags)) {
2321
			spin_unlock_irq(&device->al_lock);
2322 2323 2324 2325
			return 0;
		}
		/* Do not slow down if app IO is already waiting for this extent */
	}
2326
	spin_unlock_irq(&device->al_lock);
2327

2328 2329
	curr_events = (int)part_stat_read(&disk->part0, sectors[0]) +
		      (int)part_stat_read(&disk->part0, sectors[1]) -
2330
			atomic_read(&device->rs_sect_ev);
2331

2332
	if (!device->rs_last_events || curr_events - device->rs_last_events > 64) {
2333 2334 2335
		unsigned long rs_left;
		int i;

2336
		device->rs_last_events = curr_events;
2337 2338 2339

		/* sync speed average over the last 2*DRBD_SYNC_MARK_STEP,
		 * approx. */
2340
		i = (device->rs_last_mark + DRBD_SYNC_MARKS-1) % DRBD_SYNC_MARKS;
2341

2342 2343
		if (device->state.conn == C_VERIFY_S || device->state.conn == C_VERIFY_T)
			rs_left = device->ov_left;
2344
		else
2345
			rs_left = drbd_bm_total_weight(device) - device->rs_failed;
2346

2347
		dt = ((long)jiffies - (long)device->rs_mark_time[i]) / HZ;
2348 2349
		if (!dt)
			dt++;
2350
		db = device->rs_mark_left[i] - rs_left;
2351 2352
		dbdt = Bit2KB(db/dt);

P
Philipp Reisner 已提交
2353
		if (dbdt > c_min_rate)
2354 2355 2356 2357 2358 2359
			throttle = 1;
	}
	return throttle;
}


2360
static int receive_DataRequest(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
2361
{
2362
	struct drbd_device *device;
P
Philipp Reisner 已提交
2363
	sector_t sector;
2364
	sector_t capacity;
2365
	struct drbd_peer_request *peer_req;
P
Philipp Reisner 已提交
2366
	struct digest_info *di = NULL;
2367
	int size, verb;
P
Philipp Reisner 已提交
2368
	unsigned int fault_type;
2369
	struct p_block_req *p =	pi->data;
2370

2371
	device = vnr_to_device(connection, pi->vnr);
2372
	if (!device)
2373
		return -EIO;
2374
	capacity = drbd_get_capacity(device->this_bdev);
P
Philipp Reisner 已提交
2375 2376 2377 2378

	sector = be64_to_cpu(p->sector);
	size   = be32_to_cpu(p->blksize);

2379
	if (size <= 0 || !IS_ALIGNED(size, 512) || size > DRBD_MAX_BIO_SIZE) {
P
Philipp Reisner 已提交
2380 2381
		dev_err(DEV, "%s:%d: sector: %llus, size: %u\n", __FILE__, __LINE__,
				(unsigned long long)sector, size);
2382
		return -EINVAL;
P
Philipp Reisner 已提交
2383 2384 2385 2386
	}
	if (sector + (size>>9) > capacity) {
		dev_err(DEV, "%s:%d: sector: %llus, size: %u\n", __FILE__, __LINE__,
				(unsigned long long)sector, size);
2387
		return -EINVAL;
P
Philipp Reisner 已提交
2388 2389
	}

2390
	if (!get_ldev_if_state(device, D_UP_TO_DATE)) {
2391
		verb = 1;
2392
		switch (pi->cmd) {
2393
		case P_DATA_REQUEST:
2394
			drbd_send_ack_rp(device, P_NEG_DREPLY, p);
2395 2396 2397 2398
			break;
		case P_RS_DATA_REQUEST:
		case P_CSUM_RS_REQUEST:
		case P_OV_REQUEST:
2399
			drbd_send_ack_rp(device, P_NEG_RS_DREPLY , p);
2400 2401 2402
			break;
		case P_OV_REPLY:
			verb = 0;
2403 2404
			dec_rs_pending(device);
			drbd_send_ack_ex(device, P_OV_RESULT, sector, size, ID_IN_SYNC);
2405 2406
			break;
		default:
2407
			BUG();
2408 2409
		}
		if (verb && __ratelimit(&drbd_ratelimit_state))
P
Philipp Reisner 已提交
2410 2411
			dev_err(DEV, "Can not satisfy peer's read request, "
			    "no local data.\n");
2412

L
Lars Ellenberg 已提交
2413
		/* drain possibly payload */
2414
		return drbd_drain_block(device, pi->size);
P
Philipp Reisner 已提交
2415 2416 2417 2418 2419
	}

	/* 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.  */
2420
	peer_req = drbd_alloc_peer_req(device, p->block_id, sector, size, GFP_NOIO);
2421
	if (!peer_req) {
2422
		put_ldev(device);
2423
		return -ENOMEM;
P
Philipp Reisner 已提交
2424 2425
	}

2426
	switch (pi->cmd) {
P
Philipp Reisner 已提交
2427
	case P_DATA_REQUEST:
2428
		peer_req->w.cb = w_e_end_data_req;
P
Philipp Reisner 已提交
2429
		fault_type = DRBD_FAULT_DT_RD;
2430 2431 2432
		/* application IO, don't drbd_rs_begin_io */
		goto submit;

P
Philipp Reisner 已提交
2433
	case P_RS_DATA_REQUEST:
2434
		peer_req->w.cb = w_e_end_rsdata_req;
P
Philipp Reisner 已提交
2435
		fault_type = DRBD_FAULT_RS_RD;
2436
		/* used in the sector offset progress display */
2437
		device->bm_resync_fo = BM_SECT_TO_BIT(sector);
P
Philipp Reisner 已提交
2438 2439 2440 2441 2442
		break;

	case P_OV_REPLY:
	case P_CSUM_RS_REQUEST:
		fault_type = DRBD_FAULT_RS_RD;
2443
		di = kmalloc(sizeof(*di) + pi->size, GFP_NOIO);
P
Philipp Reisner 已提交
2444 2445 2446
		if (!di)
			goto out_free_e;

2447
		di->digest_size = pi->size;
P
Philipp Reisner 已提交
2448 2449
		di->digest = (((char *)di)+sizeof(struct digest_info));

2450 2451
		peer_req->digest = di;
		peer_req->flags |= EE_HAS_DIGEST;
2452

2453
		if (drbd_recv_all(device->connection, di->digest, pi->size))
P
Philipp Reisner 已提交
2454 2455
			goto out_free_e;

2456
		if (pi->cmd == P_CSUM_RS_REQUEST) {
2457
			D_ASSERT(device->connection->agreed_pro_version >= 89);
2458
			peer_req->w.cb = w_e_end_csum_rs_req;
2459
			/* used in the sector offset progress display */
2460
			device->bm_resync_fo = BM_SECT_TO_BIT(sector);
2461
		} else if (pi->cmd == P_OV_REPLY) {
2462
			/* track progress, we may need to throttle */
2463
			atomic_add(size >> 9, &device->rs_sect_in);
2464
			peer_req->w.cb = w_e_end_ov_reply;
2465
			dec_rs_pending(device);
2466 2467 2468
			/* drbd_rs_begin_io done when we sent this request,
			 * but accounting still needs to be done. */
			goto submit_for_resync;
P
Philipp Reisner 已提交
2469 2470 2471 2472
		}
		break;

	case P_OV_REQUEST:
2473
		if (device->ov_start_sector == ~(sector_t)0 &&
2474
		    device->connection->agreed_pro_version >= 90) {
2475 2476
			unsigned long now = jiffies;
			int i;
2477 2478 2479 2480
			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;
2481
			for (i = 0; i < DRBD_SYNC_MARKS; i++) {
2482 2483
				device->rs_mark_left[i] = device->ov_left;
				device->rs_mark_time[i] = now;
2484
			}
P
Philipp Reisner 已提交
2485 2486 2487
			dev_info(DEV, "Online Verify start sector: %llu\n",
					(unsigned long long)sector);
		}
2488
		peer_req->w.cb = w_e_end_ov_req;
P
Philipp Reisner 已提交
2489 2490 2491 2492
		fault_type = DRBD_FAULT_RS_RD;
		break;

	default:
2493
		BUG();
P
Philipp Reisner 已提交
2494 2495
	}

2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517
	/* 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.
	 */
2518
	if (device->state.peer != R_PRIMARY && drbd_rs_should_slow_down(device, sector))
2519
		schedule_timeout_uninterruptible(HZ/10);
2520
	if (drbd_rs_begin_io(device, sector))
2521
		goto out_free_e;
P
Philipp Reisner 已提交
2522

2523
submit_for_resync:
2524
	atomic_add(size >> 9, &device->rs_sect_ev);
2525

2526
submit:
2527
	inc_unacked(device);
2528
	spin_lock_irq(&device->connection->req_lock);
2529
	list_add_tail(&peer_req->w.list, &device->read_ee);
2530
	spin_unlock_irq(&device->connection->req_lock);
P
Philipp Reisner 已提交
2531

2532
	if (drbd_submit_peer_request(device, peer_req, READ, fault_type) == 0)
2533
		return 0;
P
Philipp Reisner 已提交
2534

2535 2536
	/* don't care for the reason here */
	dev_err(DEV, "submit failed, triggering re-connect\n");
2537
	spin_lock_irq(&device->connection->req_lock);
2538
	list_del(&peer_req->w.list);
2539
	spin_unlock_irq(&device->connection->req_lock);
2540 2541
	/* no drbd_rs_complete_io(), we are dropping the connection anyways */

P
Philipp Reisner 已提交
2542
out_free_e:
2543 2544
	put_ldev(device);
	drbd_free_peer_req(device, peer_req);
2545
	return -EIO;
P
Philipp Reisner 已提交
2546 2547
}

2548
static int drbd_asb_recover_0p(struct drbd_device *device) __must_hold(local)
P
Philipp Reisner 已提交
2549 2550 2551
{
	int self, peer, rv = -100;
	unsigned long ch_self, ch_peer;
2552
	enum drbd_after_sb_p after_sb_0p;
P
Philipp Reisner 已提交
2553

2554 2555
	self = device->ldev->md.uuid[UI_BITMAP] & 1;
	peer = device->p_uuid[UI_BITMAP] & 1;
P
Philipp Reisner 已提交
2556

2557 2558
	ch_peer = device->p_uuid[UI_SIZE];
	ch_self = device->comm_bm_set;
P
Philipp Reisner 已提交
2559

2560
	rcu_read_lock();
2561
	after_sb_0p = rcu_dereference(device->connection->net_conf)->after_sb_0p;
2562 2563
	rcu_read_unlock();
	switch (after_sb_0p) {
P
Philipp Reisner 已提交
2564 2565 2566
	case ASB_CONSENSUS:
	case ASB_DISCARD_SECONDARY:
	case ASB_CALL_HELPER:
2567
	case ASB_VIOLENTLY:
P
Philipp Reisner 已提交
2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591
		dev_err(DEV, "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... */
L
Lars Ellenberg 已提交
2592
		dev_warn(DEV, "Discard younger/older primary did not find a decision\n"
P
Philipp Reisner 已提交
2593 2594 2595
		     "Using discard-least-changes instead\n");
	case ASB_DISCARD_ZERO_CHG:
		if (ch_peer == 0 && ch_self == 0) {
2596
			rv = test_bit(RESOLVE_CONFLICTS, &device->connection->flags)
P
Philipp Reisner 已提交
2597 2598 2599 2600 2601 2602
				? -1 : 1;
			break;
		} else {
			if (ch_peer == 0) { rv =  1; break; }
			if (ch_self == 0) { rv = -1; break; }
		}
2603
		if (after_sb_0p == ASB_DISCARD_ZERO_CHG)
P
Philipp Reisner 已提交
2604 2605 2606 2607 2608 2609 2610 2611
			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. */
2612
			rv = test_bit(RESOLVE_CONFLICTS, &device->connection->flags)
P
Philipp Reisner 已提交
2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624
				? -1 : 1;
		break;
	case ASB_DISCARD_LOCAL:
		rv = -1;
		break;
	case ASB_DISCARD_REMOTE:
		rv =  1;
	}

	return rv;
}

2625
static int drbd_asb_recover_1p(struct drbd_device *device) __must_hold(local)
P
Philipp Reisner 已提交
2626
{
2627
	int hg, rv = -100;
2628
	enum drbd_after_sb_p after_sb_1p;
P
Philipp Reisner 已提交
2629

2630
	rcu_read_lock();
2631
	after_sb_1p = rcu_dereference(device->connection->net_conf)->after_sb_1p;
2632 2633
	rcu_read_unlock();
	switch (after_sb_1p) {
P
Philipp Reisner 已提交
2634 2635 2636 2637 2638
	case ASB_DISCARD_YOUNGER_PRI:
	case ASB_DISCARD_OLDER_PRI:
	case ASB_DISCARD_LEAST_CHG:
	case ASB_DISCARD_LOCAL:
	case ASB_DISCARD_REMOTE:
2639
	case ASB_DISCARD_ZERO_CHG:
P
Philipp Reisner 已提交
2640 2641 2642 2643 2644
		dev_err(DEV, "Configuration error.\n");
		break;
	case ASB_DISCONNECT:
		break;
	case ASB_CONSENSUS:
2645 2646
		hg = drbd_asb_recover_0p(device);
		if (hg == -1 && device->state.role == R_SECONDARY)
P
Philipp Reisner 已提交
2647
			rv = hg;
2648
		if (hg == 1  && device->state.role == R_PRIMARY)
P
Philipp Reisner 已提交
2649 2650 2651
			rv = hg;
		break;
	case ASB_VIOLENTLY:
2652
		rv = drbd_asb_recover_0p(device);
P
Philipp Reisner 已提交
2653 2654
		break;
	case ASB_DISCARD_SECONDARY:
2655
		return device->state.role == R_PRIMARY ? 1 : -1;
P
Philipp Reisner 已提交
2656
	case ASB_CALL_HELPER:
2657 2658
		hg = drbd_asb_recover_0p(device);
		if (hg == -1 && device->state.role == R_PRIMARY) {
2659 2660
			enum drbd_state_rv rv2;

P
Philipp Reisner 已提交
2661 2662 2663
			 /* 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. */
2664
			rv2 = drbd_change_state(device, CS_VERBOSE, NS(role, R_SECONDARY));
2665
			if (rv2 != SS_SUCCESS) {
2666
				drbd_khelper(device, "pri-lost-after-sb");
P
Philipp Reisner 已提交
2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677
			} else {
				dev_warn(DEV, "Successfully gave up primary role.\n");
				rv = hg;
			}
		} else
			rv = hg;
	}

	return rv;
}

2678
static int drbd_asb_recover_2p(struct drbd_device *device) __must_hold(local)
P
Philipp Reisner 已提交
2679
{
2680
	int hg, rv = -100;
2681
	enum drbd_after_sb_p after_sb_2p;
P
Philipp Reisner 已提交
2682

2683
	rcu_read_lock();
2684
	after_sb_2p = rcu_dereference(device->connection->net_conf)->after_sb_2p;
2685 2686
	rcu_read_unlock();
	switch (after_sb_2p) {
P
Philipp Reisner 已提交
2687 2688 2689 2690 2691 2692 2693
	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:
2694
	case ASB_DISCARD_ZERO_CHG:
P
Philipp Reisner 已提交
2695 2696 2697
		dev_err(DEV, "Configuration error.\n");
		break;
	case ASB_VIOLENTLY:
2698
		rv = drbd_asb_recover_0p(device);
P
Philipp Reisner 已提交
2699 2700 2701 2702
		break;
	case ASB_DISCONNECT:
		break;
	case ASB_CALL_HELPER:
2703
		hg = drbd_asb_recover_0p(device);
P
Philipp Reisner 已提交
2704
		if (hg == -1) {
2705 2706
			enum drbd_state_rv rv2;

P
Philipp Reisner 已提交
2707 2708 2709
			 /* 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. */
2710
			rv2 = drbd_change_state(device, CS_VERBOSE, NS(role, R_SECONDARY));
2711
			if (rv2 != SS_SUCCESS) {
2712
				drbd_khelper(device, "pri-lost-after-sb");
P
Philipp Reisner 已提交
2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723
			} else {
				dev_warn(DEV, "Successfully gave up primary role.\n");
				rv = hg;
			}
		} else
			rv = hg;
	}

	return rv;
}

2724
static void drbd_uuid_dump(struct drbd_device *device, char *text, u64 *uuid,
P
Philipp Reisner 已提交
2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 2748 2749
			   u64 bits, u64 flags)
{
	if (!uuid) {
		dev_info(DEV, "%s uuid info vanished while I was looking!\n", text);
		return;
	}
	dev_info(DEV, "%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
2750 2751
-1091   requires proto 91
-1096   requires proto 96
P
Philipp Reisner 已提交
2752
 */
2753
static int drbd_uuid_compare(struct drbd_device *device, int *rule_nr) __must_hold(local)
P
Philipp Reisner 已提交
2754 2755 2756 2757
{
	u64 self, peer;
	int i, j;

2758 2759
	self = device->ldev->md.uuid[UI_CURRENT] & ~((u64)1);
	peer = device->p_uuid[UI_CURRENT] & ~((u64)1);
P
Philipp Reisner 已提交
2760 2761 2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772 2773 2774 2775 2776 2777

	*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 */

2778
		if (device->p_uuid[UI_BITMAP] == (u64)0 && device->ldev->md.uuid[UI_BITMAP] != (u64)0) {
P
Philipp Reisner 已提交
2779

2780
			if (device->connection->agreed_pro_version < 91)
2781
				return -1091;
P
Philipp Reisner 已提交
2782

2783 2784
			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))) {
P
Philipp Reisner 已提交
2785
				dev_info(DEV, "was SyncSource, missed the resync finished event, corrected myself:\n");
2786 2787 2788
				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;
P
Philipp Reisner 已提交
2789

2790 2791
				drbd_uuid_dump(device, "self", device->ldev->md.uuid,
					       device->state.disk >= D_NEGOTIATING ? drbd_bm_total_weight(device) : 0, 0);
P
Philipp Reisner 已提交
2792 2793 2794 2795 2796 2797 2798 2799 2800
				*rule_nr = 34;
			} else {
				dev_info(DEV, "was SyncSource (peer failed to write sync_uuid)\n");
				*rule_nr = 36;
			}

			return 1;
		}

2801
		if (device->ldev->md.uuid[UI_BITMAP] == (u64)0 && device->p_uuid[UI_BITMAP] != (u64)0) {
P
Philipp Reisner 已提交
2802

2803
			if (device->connection->agreed_pro_version < 91)
2804
				return -1091;
P
Philipp Reisner 已提交
2805

2806 2807
			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))) {
P
Philipp Reisner 已提交
2808 2809
				dev_info(DEV, "was SyncTarget, peer missed the resync finished event, corrected peer:\n");

2810 2811 2812
				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;
P
Philipp Reisner 已提交
2813

2814
				drbd_uuid_dump(device, "peer", device->p_uuid, device->p_uuid[UI_SIZE], device->p_uuid[UI_FLAGS]);
P
Philipp Reisner 已提交
2815 2816 2817 2818 2819 2820 2821 2822 2823 2824
				*rule_nr = 35;
			} else {
				dev_info(DEV, "was SyncTarget (failed to write sync_uuid)\n");
				*rule_nr = 37;
			}

			return -1;
		}

		/* Common power [off|failure] */
2825 2826
		rct = (test_bit(CRASHED_PRIMARY, &device->flags) ? 1 : 0) +
			(device->p_uuid[UI_FLAGS] & 2);
P
Philipp Reisner 已提交
2827 2828 2829 2830 2831 2832 2833 2834 2835
		/* 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 */
2836
			dc = test_bit(RESOLVE_CONFLICTS, &device->connection->flags);
P
Philipp Reisner 已提交
2837 2838 2839 2840 2841
			return dc ? -1 : 1;
		}
	}

	*rule_nr = 50;
2842
	peer = device->p_uuid[UI_BITMAP] & ~((u64)1);
P
Philipp Reisner 已提交
2843 2844 2845 2846
	if (self == peer)
		return -1;

	*rule_nr = 51;
2847
	peer = device->p_uuid[UI_HISTORY_START] & ~((u64)1);
P
Philipp Reisner 已提交
2848
	if (self == peer) {
2849
		if (device->connection->agreed_pro_version < 96 ?
2850 2851 2852
		    (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))) {
P
Philipp Reisner 已提交
2853 2854 2855
			/* The last P_SYNC_UUID did not get though. Undo the last start of
			   resync as sync source modifications of the peer's UUIDs. */

2856
			if (device->connection->agreed_pro_version < 91)
2857
				return -1091;
P
Philipp Reisner 已提交
2858

2859 2860
			device->p_uuid[UI_BITMAP] = device->p_uuid[UI_HISTORY_START];
			device->p_uuid[UI_HISTORY_START] = device->p_uuid[UI_HISTORY_START + 1];
2861

2862
			dev_info(DEV, "Lost last syncUUID packet, corrected:\n");
2863
			drbd_uuid_dump(device, "peer", device->p_uuid, device->p_uuid[UI_SIZE], device->p_uuid[UI_FLAGS]);
2864

P
Philipp Reisner 已提交
2865 2866 2867 2868 2869
			return -1;
		}
	}

	*rule_nr = 60;
2870
	self = device->ldev->md.uuid[UI_CURRENT] & ~((u64)1);
P
Philipp Reisner 已提交
2871
	for (i = UI_HISTORY_START; i <= UI_HISTORY_END; i++) {
2872
		peer = device->p_uuid[i] & ~((u64)1);
P
Philipp Reisner 已提交
2873 2874 2875 2876 2877
		if (self == peer)
			return -2;
	}

	*rule_nr = 70;
2878 2879
	self = device->ldev->md.uuid[UI_BITMAP] & ~((u64)1);
	peer = device->p_uuid[UI_CURRENT] & ~((u64)1);
P
Philipp Reisner 已提交
2880 2881 2882 2883
	if (self == peer)
		return 1;

	*rule_nr = 71;
2884
	self = device->ldev->md.uuid[UI_HISTORY_START] & ~((u64)1);
P
Philipp Reisner 已提交
2885
	if (self == peer) {
2886
		if (device->connection->agreed_pro_version < 96 ?
2887 2888 2889
		    (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))) {
P
Philipp Reisner 已提交
2890 2891 2892
			/* The last P_SYNC_UUID did not get though. Undo the last start of
			   resync as sync source modifications of our UUIDs. */

2893
			if (device->connection->agreed_pro_version < 91)
2894
				return -1091;
P
Philipp Reisner 已提交
2895

2896 2897
			__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]);
P
Philipp Reisner 已提交
2898

2899
			dev_info(DEV, "Last syncUUID did not get through, corrected:\n");
2900 2901
			drbd_uuid_dump(device, "self", device->ldev->md.uuid,
				       device->state.disk >= D_NEGOTIATING ? drbd_bm_total_weight(device) : 0, 0);
P
Philipp Reisner 已提交
2902 2903 2904 2905 2906 2907 2908

			return 1;
		}
	}


	*rule_nr = 80;
2909
	peer = device->p_uuid[UI_CURRENT] & ~((u64)1);
P
Philipp Reisner 已提交
2910
	for (i = UI_HISTORY_START; i <= UI_HISTORY_END; i++) {
2911
		self = device->ldev->md.uuid[i] & ~((u64)1);
P
Philipp Reisner 已提交
2912 2913 2914 2915 2916
		if (self == peer)
			return 2;
	}

	*rule_nr = 90;
2917 2918
	self = device->ldev->md.uuid[UI_BITMAP] & ~((u64)1);
	peer = device->p_uuid[UI_BITMAP] & ~((u64)1);
P
Philipp Reisner 已提交
2919 2920 2921 2922 2923
	if (self == peer && self != ((u64)0))
		return 100;

	*rule_nr = 100;
	for (i = UI_HISTORY_START; i <= UI_HISTORY_END; i++) {
2924
		self = device->ldev->md.uuid[i] & ~((u64)1);
P
Philipp Reisner 已提交
2925
		for (j = UI_HISTORY_START; j <= UI_HISTORY_END; j++) {
2926
			peer = device->p_uuid[j] & ~((u64)1);
P
Philipp Reisner 已提交
2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937
			if (self == peer)
				return -100;
		}
	}

	return -1000;
}

/* drbd_sync_handshake() returns the new conn state on success, or
   CONN_MASK (-1) on failure.
 */
2938
static enum drbd_conns drbd_sync_handshake(struct drbd_device *device, enum drbd_role peer_role,
P
Philipp Reisner 已提交
2939 2940 2941 2942
					   enum drbd_disk_state peer_disk) __must_hold(local)
{
	enum drbd_conns rv = C_MASK;
	enum drbd_disk_state mydisk;
2943
	struct net_conf *nc;
2944
	int hg, rule_nr, rr_conflict, tentative;
P
Philipp Reisner 已提交
2945

2946
	mydisk = device->state.disk;
P
Philipp Reisner 已提交
2947
	if (mydisk == D_NEGOTIATING)
2948
		mydisk = device->new_state_tmp.disk;
P
Philipp Reisner 已提交
2949 2950

	dev_info(DEV, "drbd_sync_handshake:\n");
2951

2952 2953 2954 2955
	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]);
P
Philipp Reisner 已提交
2956

2957 2958
	hg = drbd_uuid_compare(device, &rule_nr);
	spin_unlock_irq(&device->ldev->md.uuid_lock);
P
Philipp Reisner 已提交
2959 2960 2961 2962 2963 2964 2965

	dev_info(DEV, "uuid_compare()=%d by rule %d\n", hg, rule_nr);

	if (hg == -1000) {
		dev_alert(DEV, "Unrelated data, aborting!\n");
		return C_MASK;
	}
2966 2967
	if (hg < -1000) {
		dev_alert(DEV, "To resolve this both sides have to support at least protocol %d\n", -hg - 1000);
P
Philipp Reisner 已提交
2968 2969 2970 2971 2972 2973 2974 2975 2976 2977 2978 2979 2980
		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;
		dev_info(DEV, "Becoming sync %s due to disk states.\n",
		     hg > 0 ? "source" : "target");
	}

2981
	if (abs(hg) == 100)
2982
		drbd_khelper(device, "initial-split-brain");
2983

2984
	rcu_read_lock();
2985
	nc = rcu_dereference(device->connection->net_conf);
2986 2987

	if (hg == 100 || (hg == -100 && nc->always_asbp)) {
2988
		int pcount = (device->state.role == R_PRIMARY)
P
Philipp Reisner 已提交
2989 2990 2991 2992 2993
			   + (peer_role == R_PRIMARY);
		int forced = (hg == -100);

		switch (pcount) {
		case 0:
2994
			hg = drbd_asb_recover_0p(device);
P
Philipp Reisner 已提交
2995 2996
			break;
		case 1:
2997
			hg = drbd_asb_recover_1p(device);
P
Philipp Reisner 已提交
2998 2999
			break;
		case 2:
3000
			hg = drbd_asb_recover_2p(device);
P
Philipp Reisner 已提交
3001 3002 3003 3004 3005 3006 3007 3008 3009 3010 3011 3012 3013 3014 3015
			break;
		}
		if (abs(hg) < 100) {
			dev_warn(DEV, "Split-Brain detected, %d primaries, "
			     "automatically solved. Sync from %s node\n",
			     pcount, (hg < 0) ? "peer" : "this");
			if (forced) {
				dev_warn(DEV, "Doing a full sync, since"
				     " UUIDs where ambiguous.\n");
				hg = hg*2;
			}
		}
	}

	if (hg == -100) {
3016
		if (test_bit(DISCARD_MY_DATA, &device->flags) && !(device->p_uuid[UI_FLAGS]&1))
P
Philipp Reisner 已提交
3017
			hg = -1;
3018
		if (!test_bit(DISCARD_MY_DATA, &device->flags) && (device->p_uuid[UI_FLAGS]&1))
P
Philipp Reisner 已提交
3019 3020 3021 3022 3023 3024 3025
			hg = 1;

		if (abs(hg) < 100)
			dev_warn(DEV, "Split-Brain detected, manually solved. "
			     "Sync from %s node\n",
			     (hg < 0) ? "peer" : "this");
	}
3026
	rr_conflict = nc->rr_conflict;
3027
	tentative = nc->tentative;
3028
	rcu_read_unlock();
P
Philipp Reisner 已提交
3029 3030

	if (hg == -100) {
3031 3032 3033 3034
		/* 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... */
3035
		dev_alert(DEV, "Split-Brain detected but unresolved, dropping connection!\n");
3036
		drbd_khelper(device, "split-brain");
P
Philipp Reisner 已提交
3037 3038 3039 3040 3041 3042 3043 3044 3045
		return C_MASK;
	}

	if (hg > 0 && mydisk <= D_INCONSISTENT) {
		dev_err(DEV, "I shall become SyncSource, but I am inconsistent!\n");
		return C_MASK;
	}

	if (hg < 0 && /* by intention we do not use mydisk here. */
3046
	    device->state.role == R_PRIMARY && device->state.disk >= D_CONSISTENT) {
3047
		switch (rr_conflict) {
P
Philipp Reisner 已提交
3048
		case ASB_CALL_HELPER:
3049
			drbd_khelper(device, "pri-lost");
P
Philipp Reisner 已提交
3050 3051 3052 3053 3054 3055 3056 3057 3058 3059
			/* fall through */
		case ASB_DISCONNECT:
			dev_err(DEV, "I shall become SyncTarget, but I am primary!\n");
			return C_MASK;
		case ASB_VIOLENTLY:
			dev_warn(DEV, "Becoming SyncTarget, violating the stable-data"
			     "assumption\n");
		}
	}

3060
	if (tentative || test_bit(CONN_DRY_RUN, &device->connection->flags)) {
3061 3062 3063 3064 3065 3066 3067 3068 3069
		if (hg == 0)
			dev_info(DEV, "dry-run connect: No resync, would become Connected immediately.\n");
		else
			dev_info(DEV, "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;
	}

P
Philipp Reisner 已提交
3070 3071
	if (abs(hg) >= 2) {
		dev_info(DEV, "Writing the whole bitmap, full sync required after drbd_sync_handshake.\n");
3072
		if (drbd_bitmap_io(device, &drbd_bmio_set_n_write, "set_n_write from sync_handshake",
3073
					BM_LOCKED_SET_ALLOWED))
P
Philipp Reisner 已提交
3074 3075 3076 3077 3078 3079 3080 3081 3082
			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;
3083
		if (drbd_bm_total_weight(device)) {
P
Philipp Reisner 已提交
3084
			dev_info(DEV, "No resync, but %lu bits in bitmap!\n",
3085
			     drbd_bm_total_weight(device));
P
Philipp Reisner 已提交
3086 3087 3088 3089 3090 3091
		}
	}

	return rv;
}

3092
static enum drbd_after_sb_p convert_after_sb(enum drbd_after_sb_p peer)
P
Philipp Reisner 已提交
3093 3094
{
	/* ASB_DISCARD_REMOTE - ASB_DISCARD_LOCAL is valid */
3095 3096
	if (peer == ASB_DISCARD_REMOTE)
		return ASB_DISCARD_LOCAL;
P
Philipp Reisner 已提交
3097 3098

	/* any other things with ASB_DISCARD_REMOTE or ASB_DISCARD_LOCAL are invalid */
3099 3100
	if (peer == ASB_DISCARD_LOCAL)
		return ASB_DISCARD_REMOTE;
P
Philipp Reisner 已提交
3101 3102

	/* everything else is valid if they are equal on both sides. */
3103
	return peer;
P
Philipp Reisner 已提交
3104 3105
}

3106
static int receive_protocol(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
3107
{
3108
	struct p_protocol *p = pi->data;
3109 3110 3111 3112
	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] = "";
3113
	struct crypto_hash *peer_integrity_tfm = NULL;
3114
	void *int_dig_in = NULL, *int_dig_vv = NULL;
P
Philipp Reisner 已提交
3115 3116 3117 3118 3119 3120

	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);
3121
	cf		= be32_to_cpu(p->conn_flags);
3122
	p_discard_my_data = cf & CF_DISCARD_MY_DATA;
3123

3124
	if (connection->agreed_pro_version >= 87) {
3125
		int err;
3126

3127
		if (pi->size > sizeof(integrity_alg))
3128
			return -EIO;
3129
		err = drbd_recv_all(connection, integrity_alg, pi->size);
3130 3131
		if (err)
			return err;
3132
		integrity_alg[SHARED_SECRET_MAX - 1] = 0;
P
Philipp Reisner 已提交
3133 3134
	}

3135
	if (pi->cmd != P_PROTOCOL_UPDATE) {
3136
		clear_bit(CONN_DRY_RUN, &connection->flags);
P
Philipp Reisner 已提交
3137

3138
		if (cf & CF_DRY_RUN)
3139
			set_bit(CONN_DRY_RUN, &connection->flags);
P
Philipp Reisner 已提交
3140

3141
		rcu_read_lock();
3142
		nc = rcu_dereference(connection->net_conf);
P
Philipp Reisner 已提交
3143

3144
		if (p_proto != nc->wire_protocol) {
3145
			conn_err(connection, "incompatible %s settings\n", "protocol");
3146 3147
			goto disconnect_rcu_unlock;
		}
P
Philipp Reisner 已提交
3148

3149
		if (convert_after_sb(p_after_sb_0p) != nc->after_sb_0p) {
3150
			conn_err(connection, "incompatible %s settings\n", "after-sb-0pri");
3151 3152
			goto disconnect_rcu_unlock;
		}
P
Philipp Reisner 已提交
3153

3154
		if (convert_after_sb(p_after_sb_1p) != nc->after_sb_1p) {
3155
			conn_err(connection, "incompatible %s settings\n", "after-sb-1pri");
3156 3157
			goto disconnect_rcu_unlock;
		}
P
Philipp Reisner 已提交
3158

3159
		if (convert_after_sb(p_after_sb_2p) != nc->after_sb_2p) {
3160
			conn_err(connection, "incompatible %s settings\n", "after-sb-2pri");
3161 3162
			goto disconnect_rcu_unlock;
		}
P
Philipp Reisner 已提交
3163

3164
		if (p_discard_my_data && nc->discard_my_data) {
3165
			conn_err(connection, "incompatible %s settings\n", "discard-my-data");
3166 3167
			goto disconnect_rcu_unlock;
		}
P
Philipp Reisner 已提交
3168

3169
		if (p_two_primaries != nc->two_primaries) {
3170
			conn_err(connection, "incompatible %s settings\n", "allow-two-primaries");
3171 3172
			goto disconnect_rcu_unlock;
		}
P
Philipp Reisner 已提交
3173

3174
		if (strcmp(integrity_alg, nc->integrity_alg)) {
3175
			conn_err(connection, "incompatible %s settings\n", "data-integrity-alg");
3176 3177
			goto disconnect_rcu_unlock;
		}
P
Philipp Reisner 已提交
3178

3179
		rcu_read_unlock();
P
Philipp Reisner 已提交
3180 3181
	}

3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192
	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.
		 */
P
Philipp Reisner 已提交
3193

3194 3195
		peer_integrity_tfm = crypto_alloc_hash(integrity_alg, 0, CRYPTO_ALG_ASYNC);
		if (!peer_integrity_tfm) {
3196
			conn_err(connection, "peer data-integrity-alg %s not supported\n",
3197 3198 3199
				 integrity_alg);
			goto disconnect;
		}
P
Philipp Reisner 已提交
3200

3201 3202 3203 3204
		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)) {
3205
			conn_err(connection, "Allocation of buffers for data integrity checking failed\n");
P
Philipp Reisner 已提交
3206 3207 3208 3209
			goto disconnect;
		}
	}

3210 3211
	new_net_conf = kmalloc(sizeof(struct net_conf), GFP_KERNEL);
	if (!new_net_conf) {
3212
		conn_err(connection, "Allocation of new net_conf failed\n");
3213 3214 3215
		goto disconnect;
	}

3216 3217 3218
	mutex_lock(&connection->data.mutex);
	mutex_lock(&connection->conf_update);
	old_net_conf = connection->net_conf;
3219 3220 3221 3222 3223 3224 3225 3226
	*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;

3227 3228 3229
	rcu_assign_pointer(connection->net_conf, new_net_conf);
	mutex_unlock(&connection->conf_update);
	mutex_unlock(&connection->data.mutex);
3230

3231 3232 3233 3234 3235 3236
	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;
3237 3238

	if (strcmp(old_net_conf->integrity_alg, integrity_alg))
3239
		conn_info(connection, "peer data-integrity-alg: %s\n",
3240 3241 3242 3243
			  integrity_alg[0] ? integrity_alg : "(none)");

	synchronize_rcu();
	kfree(old_net_conf);
3244
	return 0;
P
Philipp Reisner 已提交
3245

3246 3247
disconnect_rcu_unlock:
	rcu_read_unlock();
P
Philipp Reisner 已提交
3248
disconnect:
3249
	crypto_free_hash(peer_integrity_tfm);
3250 3251
	kfree(int_dig_in);
	kfree(int_dig_vv);
3252
	conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_HARD);
3253
	return -EIO;
P
Philipp Reisner 已提交
3254 3255 3256 3257 3258 3259 3260
}

/* 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. */
3261
static
3262
struct crypto_hash *drbd_crypto_alloc_digest_safe(const struct drbd_device *device,
P
Philipp Reisner 已提交
3263 3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278
		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)) {
		dev_err(DEV, "Can not allocate \"%s\" as %s (reason: %ld)\n",
			alg, name, PTR_ERR(tfm));
		return tfm;
	}
	return tfm;
}

3279
static int ignore_remaining_packet(struct drbd_connection *connection, struct packet_info *pi)
3280
{
3281
	void *buffer = connection->data.rbuf;
3282 3283 3284 3285
	int size = pi->size;

	while (size) {
		int s = min_t(int, size, DRBD_SOCKET_BUFFER_SIZE);
3286
		s = drbd_recv(connection, buffer, s);
3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309
		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.)
 */
3310
static int config_unknown_volume(struct drbd_connection *connection, struct packet_info *pi)
3311
{
3312
	conn_warn(connection, "%s packet received for volume %u, which is not configured locally\n",
3313
		  cmdname(pi->cmd), pi->vnr);
3314
	return ignore_remaining_packet(connection, pi);
3315 3316
}

3317
static int receive_SyncParam(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
3318
{
3319
	struct drbd_device *device;
3320
	struct p_rs_param_95 *p;
P
Philipp Reisner 已提交
3321 3322 3323
	unsigned int header_size, data_size, exp_max_sz;
	struct crypto_hash *verify_tfm = NULL;
	struct crypto_hash *csums_tfm = NULL;
3324
	struct net_conf *old_net_conf, *new_net_conf = NULL;
P
Philipp Reisner 已提交
3325
	struct disk_conf *old_disk_conf = NULL, *new_disk_conf = NULL;
3326
	const int apv = connection->agreed_pro_version;
P
Philipp Reisner 已提交
3327
	struct fifo_buffer *old_plan = NULL, *new_plan = NULL;
3328
	int fifo_size = 0;
3329
	int err;
P
Philipp Reisner 已提交
3330

3331
	device = vnr_to_device(connection, pi->vnr);
3332
	if (!device)
3333
		return config_unknown_volume(connection, pi);
P
Philipp Reisner 已提交
3334 3335 3336 3337

	exp_max_sz  = apv <= 87 ? sizeof(struct p_rs_param)
		    : apv == 88 ? sizeof(struct p_rs_param)
					+ SHARED_SECRET_MAX
3338 3339
		    : apv <= 94 ? sizeof(struct p_rs_param_89)
		    : /* apv >= 95 */ sizeof(struct p_rs_param_95);
P
Philipp Reisner 已提交
3340

3341
	if (pi->size > exp_max_sz) {
P
Philipp Reisner 已提交
3342
		dev_err(DEV, "SyncParam packet too long: received %u, expected <= %u bytes\n",
3343
		    pi->size, exp_max_sz);
3344
		return -EIO;
P
Philipp Reisner 已提交
3345 3346 3347
	}

	if (apv <= 88) {
3348
		header_size = sizeof(struct p_rs_param);
3349
		data_size = pi->size - header_size;
3350
	} else if (apv <= 94) {
3351
		header_size = sizeof(struct p_rs_param_89);
3352
		data_size = pi->size - header_size;
P
Philipp Reisner 已提交
3353
		D_ASSERT(data_size == 0);
3354
	} else {
3355
		header_size = sizeof(struct p_rs_param_95);
3356
		data_size = pi->size - header_size;
P
Philipp Reisner 已提交
3357 3358 3359 3360
		D_ASSERT(data_size == 0);
	}

	/* initialize verify_alg and csums_alg */
3361
	p = pi->data;
P
Philipp Reisner 已提交
3362 3363
	memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX);

3364
	err = drbd_recv_all(device->connection, p, header_size);
3365 3366
	if (err)
		return err;
P
Philipp Reisner 已提交
3367

3368 3369
	mutex_lock(&device->connection->conf_update);
	old_net_conf = device->connection->net_conf;
3370
	if (get_ldev(device)) {
P
Philipp Reisner 已提交
3371 3372
		new_disk_conf = kzalloc(sizeof(struct disk_conf), GFP_KERNEL);
		if (!new_disk_conf) {
3373
			put_ldev(device);
3374
			mutex_unlock(&device->connection->conf_update);
P
Philipp Reisner 已提交
3375 3376 3377
			dev_err(DEV, "Allocation of new disk_conf failed\n");
			return -ENOMEM;
		}
P
Philipp Reisner 已提交
3378

3379
		old_disk_conf = device->ldev->disk_conf;
P
Philipp Reisner 已提交
3380
		*new_disk_conf = *old_disk_conf;
P
Philipp Reisner 已提交
3381

3382
		new_disk_conf->resync_rate = be32_to_cpu(p->resync_rate);
P
Philipp Reisner 已提交
3383
	}
P
Philipp Reisner 已提交
3384 3385 3386

	if (apv >= 88) {
		if (apv == 88) {
3387 3388 3389 3390
			if (data_size > SHARED_SECRET_MAX || data_size == 0) {
				dev_err(DEV, "verify-alg of wrong size, "
					"peer wants %u, accepting only up to %u byte\n",
					data_size, SHARED_SECRET_MAX);
P
Philipp Reisner 已提交
3391 3392
				err = -EIO;
				goto reconnect;
P
Philipp Reisner 已提交
3393 3394
			}

3395
			err = drbd_recv_all(device->connection, p->verify_alg, data_size);
P
Philipp Reisner 已提交
3396 3397
			if (err)
				goto reconnect;
P
Philipp Reisner 已提交
3398 3399 3400 3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411
			/* we expect NUL terminated string */
			/* but just in case someone tries to be evil */
			D_ASSERT(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(p->verify_alg[SHARED_SECRET_MAX-1] == 0);
			D_ASSERT(p->csums_alg[SHARED_SECRET_MAX-1] == 0);
			p->verify_alg[SHARED_SECRET_MAX-1] = 0;
			p->csums_alg[SHARED_SECRET_MAX-1] = 0;
		}

3412
		if (strcmp(old_net_conf->verify_alg, p->verify_alg)) {
3413
			if (device->state.conn == C_WF_REPORT_PARAMS) {
P
Philipp Reisner 已提交
3414
				dev_err(DEV, "Different verify-alg settings. me=\"%s\" peer=\"%s\"\n",
3415
				    old_net_conf->verify_alg, p->verify_alg);
P
Philipp Reisner 已提交
3416 3417
				goto disconnect;
			}
3418
			verify_tfm = drbd_crypto_alloc_digest_safe(device,
P
Philipp Reisner 已提交
3419 3420 3421 3422 3423 3424 3425
					p->verify_alg, "verify-alg");
			if (IS_ERR(verify_tfm)) {
				verify_tfm = NULL;
				goto disconnect;
			}
		}

3426
		if (apv >= 89 && strcmp(old_net_conf->csums_alg, p->csums_alg)) {
3427
			if (device->state.conn == C_WF_REPORT_PARAMS) {
P
Philipp Reisner 已提交
3428
				dev_err(DEV, "Different csums-alg settings. me=\"%s\" peer=\"%s\"\n",
3429
				    old_net_conf->csums_alg, p->csums_alg);
P
Philipp Reisner 已提交
3430 3431
				goto disconnect;
			}
3432
			csums_tfm = drbd_crypto_alloc_digest_safe(device,
P
Philipp Reisner 已提交
3433 3434 3435 3436 3437 3438 3439
					p->csums_alg, "csums-alg");
			if (IS_ERR(csums_tfm)) {
				csums_tfm = NULL;
				goto disconnect;
			}
		}

P
Philipp Reisner 已提交
3440
		if (apv > 94 && new_disk_conf) {
P
Philipp Reisner 已提交
3441 3442 3443 3444
			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);
3445

P
Philipp Reisner 已提交
3446
			fifo_size = (new_disk_conf->c_plan_ahead * 10 * SLEEP_TIME) / HZ;
3447
			if (fifo_size != device->rs_plan_s->size) {
P
Philipp Reisner 已提交
3448 3449
				new_plan = fifo_alloc(fifo_size);
				if (!new_plan) {
3450
					dev_err(DEV, "kmalloc of fifo_buffer failed");
3451
					put_ldev(device);
3452 3453 3454
					goto disconnect;
				}
			}
3455
		}
P
Philipp Reisner 已提交
3456

3457
		if (verify_tfm || csums_tfm) {
3458 3459
			new_net_conf = kzalloc(sizeof(struct net_conf), GFP_KERNEL);
			if (!new_net_conf) {
3460 3461 3462 3463
				dev_err(DEV, "Allocation of new net_conf failed\n");
				goto disconnect;
			}

3464
			*new_net_conf = *old_net_conf;
3465 3466

			if (verify_tfm) {
3467 3468
				strcpy(new_net_conf->verify_alg, p->verify_alg);
				new_net_conf->verify_alg_len = strlen(p->verify_alg) + 1;
3469 3470
				crypto_free_hash(device->connection->verify_tfm);
				device->connection->verify_tfm = verify_tfm;
3471 3472 3473
				dev_info(DEV, "using verify-alg: \"%s\"\n", p->verify_alg);
			}
			if (csums_tfm) {
3474 3475
				strcpy(new_net_conf->csums_alg, p->csums_alg);
				new_net_conf->csums_alg_len = strlen(p->csums_alg) + 1;
3476 3477
				crypto_free_hash(device->connection->csums_tfm);
				device->connection->csums_tfm = csums_tfm;
3478 3479
				dev_info(DEV, "using csums-alg: \"%s\"\n", p->csums_alg);
			}
3480
			rcu_assign_pointer(connection->net_conf, new_net_conf);
3481
		}
P
Philipp Reisner 已提交
3482 3483
	}

P
Philipp Reisner 已提交
3484
	if (new_disk_conf) {
3485 3486
		rcu_assign_pointer(device->ldev->disk_conf, new_disk_conf);
		put_ldev(device);
P
Philipp Reisner 已提交
3487 3488 3489
	}

	if (new_plan) {
3490 3491
		old_plan = device->rs_plan_s;
		rcu_assign_pointer(device->rs_plan_s, new_plan);
P
Philipp Reisner 已提交
3492
	}
P
Philipp Reisner 已提交
3493

3494
	mutex_unlock(&device->connection->conf_update);
P
Philipp Reisner 已提交
3495 3496 3497 3498
	synchronize_rcu();
	if (new_net_conf)
		kfree(old_net_conf);
	kfree(old_disk_conf);
P
Philipp Reisner 已提交
3499
	kfree(old_plan);
P
Philipp Reisner 已提交
3500

3501
	return 0;
P
Philipp Reisner 已提交
3502

P
Philipp Reisner 已提交
3503 3504
reconnect:
	if (new_disk_conf) {
3505
		put_ldev(device);
P
Philipp Reisner 已提交
3506 3507
		kfree(new_disk_conf);
	}
3508
	mutex_unlock(&device->connection->conf_update);
P
Philipp Reisner 已提交
3509 3510
	return -EIO;

P
Philipp Reisner 已提交
3511
disconnect:
P
Philipp Reisner 已提交
3512 3513
	kfree(new_plan);
	if (new_disk_conf) {
3514
		put_ldev(device);
P
Philipp Reisner 已提交
3515 3516
		kfree(new_disk_conf);
	}
3517
	mutex_unlock(&device->connection->conf_update);
P
Philipp Reisner 已提交
3518 3519 3520 3521 3522
	/* 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);
3523
	conn_request_state(device->connection, NS(conn, C_DISCONNECTING), CS_HARD);
3524
	return -EIO;
P
Philipp Reisner 已提交
3525 3526 3527
}

/* warn if the arguments differ by more than 12.5% */
3528
static void warn_if_differ_considerably(struct drbd_device *device,
P
Philipp Reisner 已提交
3529 3530 3531 3532 3533 3534 3535 3536 3537 3538 3539
	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))
		dev_warn(DEV, "Considerable difference in %s: %llus vs. %llus\n", s,
		     (unsigned long long)a, (unsigned long long)b);
}

3540
static int receive_sizes(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
3541
{
3542
	struct drbd_device *device;
3543
	struct p_sizes *p = pi->data;
3544
	enum determine_dev_size dd = DS_UNCHANGED;
P
Philipp Reisner 已提交
3545 3546
	sector_t p_size, p_usize, my_usize;
	int ldsc = 0; /* local disk size changed */
3547
	enum dds_flags ddsf;
P
Philipp Reisner 已提交
3548

3549
	device = vnr_to_device(connection, pi->vnr);
3550
	if (!device)
3551
		return config_unknown_volume(connection, pi);
3552

P
Philipp Reisner 已提交
3553 3554 3555 3556 3557
	p_size = be64_to_cpu(p->d_size);
	p_usize = be64_to_cpu(p->u_size);

	/* just store the peer's disk size for now.
	 * we still need to figure out whether we accept that. */
3558
	device->p_size = p_size;
P
Philipp Reisner 已提交
3559

3560
	if (get_ldev(device)) {
P
Philipp Reisner 已提交
3561
		rcu_read_lock();
3562
		my_usize = rcu_dereference(device->ldev->disk_conf)->disk_size;
P
Philipp Reisner 已提交
3563 3564
		rcu_read_unlock();

3565 3566 3567
		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
Philipp Reisner 已提交
3568
					    p_usize, my_usize);
P
Philipp Reisner 已提交
3569 3570 3571

		/* if this is the first connect, or an otherwise expected
		 * param exchange, choose the minimum */
3572
		if (device->state.conn == C_WF_REPORT_PARAMS)
P
Philipp Reisner 已提交
3573
			p_usize = min_not_zero(my_usize, p_usize);
P
Philipp Reisner 已提交
3574 3575 3576

		/* Never shrink a device with usable data during connect.
		   But allow online shrinking if we are connected. */
3577 3578 3579 3580
		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) {
P
Philipp Reisner 已提交
3581
			dev_err(DEV, "The peer's disk size is too small!\n");
3582
			conn_request_state(device->connection, NS(conn, C_DISCONNECTING), CS_HARD);
3583
			put_ldev(device);
3584
			return -EIO;
P
Philipp Reisner 已提交
3585
		}
P
Philipp Reisner 已提交
3586 3587 3588 3589 3590 3591 3592

		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) {
				dev_err(DEV, "Allocation of new disk_conf failed\n");
3593
				put_ldev(device);
P
Philipp Reisner 已提交
3594 3595 3596
				return -ENOMEM;
			}

3597
			mutex_lock(&device->connection->conf_update);
3598
			old_disk_conf = device->ldev->disk_conf;
P
Philipp Reisner 已提交
3599 3600 3601
			*new_disk_conf = *old_disk_conf;
			new_disk_conf->disk_size = p_usize;

3602
			rcu_assign_pointer(device->ldev->disk_conf, new_disk_conf);
3603
			mutex_unlock(&device->connection->conf_update);
P
Philipp Reisner 已提交
3604 3605 3606 3607 3608
			synchronize_rcu();
			kfree(old_disk_conf);

			dev_info(DEV, "Peer sets u_size to %lu sectors\n",
				 (unsigned long)my_usize);
P
Philipp Reisner 已提交
3609
		}
P
Philipp Reisner 已提交
3610

3611
		put_ldev(device);
P
Philipp Reisner 已提交
3612 3613
	}

3614
	ddsf = be16_to_cpu(p->dds_flags);
3615 3616 3617
	if (get_ldev(device)) {
		dd = drbd_determine_dev_size(device, ddsf, NULL);
		put_ldev(device);
3618
		if (dd == DS_ERROR)
3619
			return -EIO;
3620
		drbd_md_sync(device);
P
Philipp Reisner 已提交
3621 3622
	} else {
		/* I am diskless, need to accept the peer's size. */
3623
		drbd_set_my_capacity(device, p_size);
P
Philipp Reisner 已提交
3624 3625
	}

3626 3627
	device->peer_max_bio_size = be32_to_cpu(p->max_bio_size);
	drbd_reconsider_max_bio_size(device);
3628

3629 3630 3631
	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);
P
Philipp Reisner 已提交
3632 3633 3634
			ldsc = 1;
		}

3635
		put_ldev(device);
P
Philipp Reisner 已提交
3636 3637
	}

3638
	if (device->state.conn > C_WF_REPORT_PARAMS) {
P
Philipp Reisner 已提交
3639
		if (be64_to_cpu(p->c_size) !=
3640
		    drbd_get_capacity(device->this_bdev) || ldsc) {
P
Philipp Reisner 已提交
3641 3642
			/* we have different sizes, probably peer
			 * needs to know my new size... */
3643
			drbd_send_sizes(device, 0, ddsf);
P
Philipp Reisner 已提交
3644
		}
3645 3646 3647 3648
		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) {
3649 3650 3651
				if (ddsf & DDSF_NO_RESYNC)
					dev_info(DEV, "Resync of new storage suppressed with --assume-clean\n");
				else
3652
					resync_after_online_grow(device);
3653
			} else
3654
				set_bit(RESYNC_AFTER_NEG, &device->flags);
P
Philipp Reisner 已提交
3655 3656 3657
		}
	}

3658
	return 0;
P
Philipp Reisner 已提交
3659 3660
}

3661
static int receive_uuids(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
3662
{
3663
	struct drbd_device *device;
3664
	struct p_uuids *p = pi->data;
P
Philipp Reisner 已提交
3665
	u64 *p_uuid;
3666
	int i, updated_uuids = 0;
P
Philipp Reisner 已提交
3667

3668
	device = vnr_to_device(connection, pi->vnr);
3669
	if (!device)
3670
		return config_unknown_volume(connection, pi);
3671

P
Philipp Reisner 已提交
3672
	p_uuid = kmalloc(sizeof(u64)*UI_EXTENDED_SIZE, GFP_NOIO);
3673 3674 3675 3676
	if (!p_uuid) {
		dev_err(DEV, "kmalloc of p_uuid failed\n");
		return false;
	}
P
Philipp Reisner 已提交
3677 3678 3679 3680

	for (i = UI_CURRENT; i < UI_EXTENDED_SIZE; i++)
		p_uuid[i] = be64_to_cpu(p->uuid[i]);

3681 3682
	kfree(device->p_uuid);
	device->p_uuid = p_uuid;
P
Philipp Reisner 已提交
3683

3684 3685 3686 3687
	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))) {
P
Philipp Reisner 已提交
3688
		dev_err(DEV, "Can only connect to data with current UUID=%016llX\n",
3689
		    (unsigned long long)device->ed_uuid);
3690
		conn_request_state(device->connection, NS(conn, C_DISCONNECTING), CS_HARD);
3691
		return -EIO;
P
Philipp Reisner 已提交
3692 3693
	}

3694
	if (get_ldev(device)) {
P
Philipp Reisner 已提交
3695
		int skip_initial_sync =
3696
			device->state.conn == C_CONNECTED &&
3697
			device->connection->agreed_pro_version >= 90 &&
3698
			device->ldev->md.uuid[UI_CURRENT] == UUID_JUST_CREATED &&
P
Philipp Reisner 已提交
3699 3700 3701
			(p_uuid[UI_FLAGS] & 8);
		if (skip_initial_sync) {
			dev_info(DEV, "Accepted new current UUID, preparing to skip initial sync\n");
3702
			drbd_bitmap_io(device, &drbd_bmio_clear_n_write,
3703 3704
					"clear_n_write from receive_uuids",
					BM_LOCKED_TEST_ALLOWED);
3705 3706 3707
			_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),
P
Philipp Reisner 已提交
3708
					CS_VERBOSE, NULL);
3709
			drbd_md_sync(device);
3710
			updated_uuids = 1;
P
Philipp Reisner 已提交
3711
		}
3712 3713 3714
		put_ldev(device);
	} else if (device->state.disk < D_INCONSISTENT &&
		   device->state.role == R_PRIMARY) {
3715 3716
		/* I am a diskless primary, the peer just created a new current UUID
		   for me. */
3717
		updated_uuids = drbd_set_ed_uuid(device, p_uuid[UI_CURRENT]);
P
Philipp Reisner 已提交
3718 3719 3720 3721 3722 3723
	}

	/* 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... */
3724 3725 3726 3727
	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]);
3728 3729

	if (updated_uuids)
3730
		drbd_print_uuids(device, "receiver updated UUIDs to");
P
Philipp Reisner 已提交
3731

3732
	return 0;
P
Philipp Reisner 已提交
3733 3734 3735 3736 3737 3738 3739 3740 3741 3742 3743
}

/**
 * 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[] = {
3744
		[C_WF_REPORT_PARAMS] = C_WF_REPORT_PARAMS,
P
Philipp Reisner 已提交
3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756 3757 3758 3759 3760 3761 3762 3763 3764 3765
		[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;
}

3766
static int receive_req_state(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
3767
{
3768
	struct drbd_device *device;
3769
	struct p_req_state *p = pi->data;
P
Philipp Reisner 已提交
3770
	union drbd_state mask, val;
3771
	enum drbd_state_rv rv;
P
Philipp Reisner 已提交
3772

3773
	device = vnr_to_device(connection, pi->vnr);
3774
	if (!device)
3775 3776
		return -EIO;

P
Philipp Reisner 已提交
3777 3778 3779
	mask.i = be32_to_cpu(p->mask);
	val.i = be32_to_cpu(p->val);

3780
	if (test_bit(RESOLVE_CONFLICTS, &device->connection->flags) &&
3781 3782
	    mutex_is_locked(device->state_mutex)) {
		drbd_send_sr_reply(device, SS_CONCURRENT_ST_CHG);
3783
		return 0;
P
Philipp Reisner 已提交
3784 3785 3786 3787 3788
	}

	mask = convert_state(mask);
	val = convert_state(val);

3789 3790
	rv = drbd_change_state(device, CS_VERBOSE, mask, val);
	drbd_send_sr_reply(device, rv);
P
Philipp Reisner 已提交
3791

3792
	drbd_md_sync(device);
P
Philipp Reisner 已提交
3793

3794
	return 0;
P
Philipp Reisner 已提交
3795 3796
}

3797
static int receive_req_conn_state(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
3798
{
3799
	struct p_req_state *p = pi->data;
P
Philipp Reisner 已提交
3800
	union drbd_state mask, val;
3801
	enum drbd_state_rv rv;
P
Philipp Reisner 已提交
3802 3803 3804 3805

	mask.i = be32_to_cpu(p->mask);
	val.i = be32_to_cpu(p->val);

3806 3807 3808
	if (test_bit(RESOLVE_CONFLICTS, &connection->flags) &&
	    mutex_is_locked(&connection->cstate_mutex)) {
		conn_send_sr_reply(connection, SS_CONCURRENT_ST_CHG);
3809
		return 0;
P
Philipp Reisner 已提交
3810 3811 3812 3813 3814
	}

	mask = convert_state(mask);
	val = convert_state(val);

3815 3816
	rv = conn_request_state(connection, mask, val, CS_VERBOSE | CS_LOCAL_ONLY | CS_IGN_OUTD_FAIL);
	conn_send_sr_reply(connection, rv);
P
Philipp Reisner 已提交
3817

3818
	return 0;
P
Philipp Reisner 已提交
3819 3820
}

3821
static int receive_state(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
3822
{
3823
	struct drbd_device *device;
3824
	struct p_state *p = pi->data;
3825
	union drbd_state os, ns, peer_state;
P
Philipp Reisner 已提交
3826
	enum drbd_disk_state real_peer_disk;
3827
	enum chg_state_flags cs_flags;
P
Philipp Reisner 已提交
3828 3829
	int rv;

3830
	device = vnr_to_device(connection, pi->vnr);
3831
	if (!device)
3832
		return config_unknown_volume(connection, pi);
3833

P
Philipp Reisner 已提交
3834 3835 3836 3837
	peer_state.i = be32_to_cpu(p->state);

	real_peer_disk = peer_state.disk;
	if (peer_state.disk == D_NEGOTIATING) {
3838
		real_peer_disk = device->p_uuid[UI_FLAGS] & 4 ? D_INCONSISTENT : D_CONSISTENT;
P
Philipp Reisner 已提交
3839 3840 3841
		dev_info(DEV, "real peer disk state = %s\n", drbd_disk_str(real_peer_disk));
	}

3842
	spin_lock_irq(&device->connection->req_lock);
P
Philipp Reisner 已提交
3843
 retry:
3844
	os = ns = drbd_read_state(device);
3845
	spin_unlock_irq(&device->connection->req_lock);
P
Philipp Reisner 已提交
3846

3847 3848 3849 3850
	/* 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)
3851
		return -ECONNRESET;
3852

3853 3854 3855 3856 3857 3858 3859 3860
	/* 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 &&
3861 3862 3863 3864 3865 3866 3867 3868 3869 3870 3871 3872 3873 3874 3875 3876
	    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) {
3877 3878
			if (drbd_bm_total_weight(device) <= device->rs_failed)
				drbd_resync_finished(device);
3879
			return 0;
3880 3881 3882
		}
	}

3883 3884 3885
	/* 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) {
3886 3887
		ov_out_of_sync_print(device);
		drbd_resync_finished(device);
3888
		return 0;
3889 3890
	}

3891 3892 3893 3894 3895 3896 3897 3898 3899
	/* 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;

3900 3901
	if (ns.conn == C_WF_REPORT_PARAMS)
		ns.conn = C_CONNECTED;
P
Philipp Reisner 已提交
3902

3903 3904 3905
	if (peer_state.conn == C_AHEAD)
		ns.conn = C_BEHIND;

3906 3907
	if (device->p_uuid && peer_state.disk >= D_NEGOTIATING &&
	    get_ldev_if_state(device, D_NEGOTIATING)) {
P
Philipp Reisner 已提交
3908 3909 3910
		int cr; /* consider resync */

		/* if we established a new connection */
3911
		cr  = (os.conn < C_CONNECTED);
P
Philipp Reisner 已提交
3912 3913
		/* if we had an established connection
		 * and one of the nodes newly attaches a disk */
3914
		cr |= (os.conn == C_CONNECTED &&
P
Philipp Reisner 已提交
3915
		       (peer_state.disk == D_NEGOTIATING ||
3916
			os.disk == D_NEGOTIATING));
P
Philipp Reisner 已提交
3917 3918
		/* if we have both been inconsistent, and the peer has been
		 * forced to be UpToDate with --overwrite-data */
3919
		cr |= test_bit(CONSIDER_RESYNC, &device->flags);
P
Philipp Reisner 已提交
3920 3921
		/* if we had been plain connected, and the admin requested to
		 * start a sync by "invalidate" or "invalidate-remote" */
3922
		cr |= (os.conn == C_CONNECTED &&
P
Philipp Reisner 已提交
3923 3924 3925 3926
				(peer_state.conn >= C_STARTING_SYNC_S &&
				 peer_state.conn <= C_WF_BITMAP_T));

		if (cr)
3927
			ns.conn = drbd_sync_handshake(device, peer_state.role, real_peer_disk);
P
Philipp Reisner 已提交
3928

3929
		put_ldev(device);
3930 3931
		if (ns.conn == C_MASK) {
			ns.conn = C_CONNECTED;
3932 3933
			if (device->state.disk == D_NEGOTIATING) {
				drbd_force_state(device, NS(disk, D_FAILED));
P
Philipp Reisner 已提交
3934 3935 3936
			} else if (peer_state.disk == D_NEGOTIATING) {
				dev_err(DEV, "Disk attach process on the peer node was aborted.\n");
				peer_state.disk = D_DISKLESS;
3937
				real_peer_disk = D_DISKLESS;
P
Philipp Reisner 已提交
3938
			} else {
3939
				if (test_and_clear_bit(CONN_DRY_RUN, &device->connection->flags))
3940
					return -EIO;
3941
				D_ASSERT(os.conn == C_WF_REPORT_PARAMS);
3942
				conn_request_state(device->connection, NS(conn, C_DISCONNECTING), CS_HARD);
3943
				return -EIO;
P
Philipp Reisner 已提交
3944 3945 3946 3947
			}
		}
	}

3948
	spin_lock_irq(&device->connection->req_lock);
3949
	if (os.i != drbd_read_state(device).i)
P
Philipp Reisner 已提交
3950
		goto retry;
3951
	clear_bit(CONSIDER_RESYNC, &device->flags);
P
Philipp Reisner 已提交
3952 3953 3954
	ns.peer = peer_state.role;
	ns.pdsk = real_peer_disk;
	ns.peer_isp = (peer_state.aftr_isp | peer_state.user_isp);
3955
	if ((ns.conn == C_CONNECTED || ns.conn == C_WF_BITMAP_S) && ns.disk == D_NEGOTIATING)
3956
		ns.disk = device->new_state_tmp.disk;
3957
	cs_flags = CS_VERBOSE + (os.conn < C_CONNECTED && ns.conn >= C_CONNECTED ? 0 : CS_HARD);
3958 3959
	if (ns.pdsk == D_CONSISTENT && drbd_suspended(device) && ns.conn == C_CONNECTED && os.conn < C_CONNECTED &&
	    test_bit(NEW_CUR_UUID, &device->flags)) {
3960
		/* Do not allow tl_restart(RESEND) for a rebooted peer. We can only allow this
3961
		   for temporal network outages! */
3962
		spin_unlock_irq(&device->connection->req_lock);
3963
		dev_err(DEV, "Aborting Connect, can not thaw IO with an only Consistent peer\n");
3964
		tl_clear(device->connection);
3965 3966
		drbd_uuid_new_current(device);
		clear_bit(NEW_CUR_UUID, &device->flags);
3967
		conn_request_state(device->connection, NS2(conn, C_PROTOCOL_ERROR, susp, 0), CS_HARD);
3968
		return -EIO;
3969
	}
3970 3971
	rv = _drbd_set_state(device, ns, cs_flags, NULL);
	ns = drbd_read_state(device);
3972
	spin_unlock_irq(&device->connection->req_lock);
P
Philipp Reisner 已提交
3973 3974

	if (rv < SS_SUCCESS) {
3975
		conn_request_state(device->connection, NS(conn, C_DISCONNECTING), CS_HARD);
3976
		return -EIO;
P
Philipp Reisner 已提交
3977 3978
	}

3979 3980
	if (os.conn > C_WF_REPORT_PARAMS) {
		if (ns.conn > C_CONNECTED && peer_state.conn <= C_CONNECTED &&
P
Philipp Reisner 已提交
3981 3982 3983 3984
		    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 */
3985 3986
			drbd_send_uuids(device);
			drbd_send_current_state(device);
P
Philipp Reisner 已提交
3987 3988 3989
		}
	}

3990
	clear_bit(DISCARD_MY_DATA, &device->flags);
P
Philipp Reisner 已提交
3991

3992
	drbd_md_sync(device); /* update connected indicator, la_size_sect, ... */
P
Philipp Reisner 已提交
3993

3994
	return 0;
P
Philipp Reisner 已提交
3995 3996
}

3997
static int receive_sync_uuid(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
3998
{
3999
	struct drbd_device *device;
4000
	struct p_rs_uuid *p = pi->data;
4001

4002
	device = vnr_to_device(connection, pi->vnr);
4003
	if (!device)
4004
		return -EIO;
P
Philipp Reisner 已提交
4005

4006 4007 4008 4009 4010
	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);
P
Philipp Reisner 已提交
4011

4012
	/* D_ASSERT( device->state.conn == C_WF_SYNC_UUID ); */
P
Philipp Reisner 已提交
4013 4014 4015

	/* Here the _drbd_uuid_ functions are right, current should
	   _not_ be rotated into the history */
4016 4017 4018
	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);
P
Philipp Reisner 已提交
4019

4020 4021
		drbd_print_uuids(device, "updated sync uuid");
		drbd_start_resync(device, C_SYNC_TARGET);
P
Philipp Reisner 已提交
4022

4023
		put_ldev(device);
P
Philipp Reisner 已提交
4024 4025 4026
	} else
		dev_err(DEV, "Ignoring SyncUUID packet!\n");

4027
	return 0;
P
Philipp Reisner 已提交
4028 4029
}

4030 4031 4032 4033 4034 4035 4036
/**
 * receive_bitmap_plain
 *
 * Return 0 when done, 1 when another iteration is needed, and a negative error
 * code upon failure.
 */
static int
4037
receive_bitmap_plain(struct drbd_device *device, unsigned int size,
4038
		     unsigned long *p, struct bm_xfer_ctx *c)
P
Philipp Reisner 已提交
4039
{
4040
	unsigned int data_size = DRBD_SOCKET_BUFFER_SIZE -
4041
				 drbd_header_size(device->connection);
4042
	unsigned int num_words = min_t(size_t, data_size / sizeof(*p),
4043
				       c->bm_words - c->word_offset);
4044
	unsigned int want = num_words * sizeof(*p);
4045
	int err;
P
Philipp Reisner 已提交
4046

4047 4048
	if (want != size) {
		dev_err(DEV, "%s:want (%u) != size (%u)\n", __func__, want, size);
4049
		return -EIO;
P
Philipp Reisner 已提交
4050 4051
	}
	if (want == 0)
4052
		return 0;
4053
	err = drbd_recv_all(device->connection, p, want);
4054
	if (err)
4055
		return err;
P
Philipp Reisner 已提交
4056

4057
	drbd_bm_merge_lel(device, c->word_offset, num_words, p);
P
Philipp Reisner 已提交
4058 4059 4060 4061 4062 4063

	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;

4064
	return 1;
P
Philipp Reisner 已提交
4065 4066
}

4067 4068 4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079 4080 4081
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;
}

4082 4083 4084 4085 4086 4087 4088
/**
 * recv_bm_rle_bits
 *
 * Return 0 when done, 1 when another iteration is needed, and a negative error
 * code upon failure.
 */
static int
4089
recv_bm_rle_bits(struct drbd_device *device,
P
Philipp Reisner 已提交
4090
		struct p_compressed_bm *p,
4091 4092
		 struct bm_xfer_ctx *c,
		 unsigned int len)
P
Philipp Reisner 已提交
4093 4094 4095 4096 4097 4098 4099
{
	struct bitstream bs;
	u64 look_ahead;
	u64 rl;
	u64 tmp;
	unsigned long s = c->bit_offset;
	unsigned long e;
4100
	int toggle = dcbp_get_start(p);
P
Philipp Reisner 已提交
4101 4102 4103
	int have;
	int bits;

4104
	bitstream_init(&bs, p->code, len, dcbp_get_pad_bits(p));
P
Philipp Reisner 已提交
4105 4106 4107

	bits = bitstream_get_bits(&bs, &look_ahead, 64);
	if (bits < 0)
4108
		return -EIO;
P
Philipp Reisner 已提交
4109 4110 4111 4112

	for (have = bits; have > 0; s += rl, toggle = !toggle) {
		bits = vli_decode_bits(&rl, look_ahead);
		if (bits <= 0)
4113
			return -EIO;
P
Philipp Reisner 已提交
4114 4115 4116 4117 4118

		if (toggle) {
			e = s + rl -1;
			if (e >= c->bm_bits) {
				dev_err(DEV, "bitmap overflow (e:%lu) while decoding bm RLE packet\n", e);
4119
				return -EIO;
P
Philipp Reisner 已提交
4120
			}
4121
			_drbd_bm_set_bits(device, s, e);
P
Philipp Reisner 已提交
4122 4123 4124 4125 4126 4127 4128
		}

		if (have < bits) {
			dev_err(DEV, "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);
4129
			return -EIO;
P
Philipp Reisner 已提交
4130
		}
4131 4132 4133 4134 4135
		/* if we consumed all 64 bits, assign 0; >> 64 is "undefined"; */
		if (likely(bits < 64))
			look_ahead >>= bits;
		else
			look_ahead = 0;
P
Philipp Reisner 已提交
4136 4137 4138 4139
		have -= bits;

		bits = bitstream_get_bits(&bs, &tmp, 64 - have);
		if (bits < 0)
4140
			return -EIO;
P
Philipp Reisner 已提交
4141 4142 4143 4144 4145 4146 4147
		look_ahead |= tmp << have;
		have += bits;
	}

	c->bit_offset = s;
	bm_xfer_ctx_bit_to_word_offset(c);

4148
	return (s != c->bm_bits);
P
Philipp Reisner 已提交
4149 4150
}

4151 4152 4153 4154 4155 4156 4157
/**
 * decode_bitmap_c
 *
 * Return 0 when done, 1 when another iteration is needed, and a negative error
 * code upon failure.
 */
static int
4158
decode_bitmap_c(struct drbd_device *device,
P
Philipp Reisner 已提交
4159
		struct p_compressed_bm *p,
4160 4161
		struct bm_xfer_ctx *c,
		unsigned int len)
P
Philipp Reisner 已提交
4162
{
4163
	if (dcbp_get_code(p) == RLE_VLI_Bits)
4164
		return recv_bm_rle_bits(device, p, c, len - sizeof(*p));
P
Philipp Reisner 已提交
4165 4166 4167 4168 4169 4170

	/* other variants had been implemented for evaluation,
	 * but have been dropped as this one turned out to be "best"
	 * during all our tests. */

	dev_err(DEV, "receive_bitmap_c: unknown encoding %u\n", p->encoding);
4171
	conn_request_state(device->connection, NS(conn, C_PROTOCOL_ERROR), CS_HARD);
4172
	return -EIO;
P
Philipp Reisner 已提交
4173 4174
}

4175
void INFO_bm_xfer_stats(struct drbd_device *device,
P
Philipp Reisner 已提交
4176 4177 4178
		const char *direction, struct bm_xfer_ctx *c)
{
	/* what would it take to transfer it "plaintext" */
4179
	unsigned int header_size = drbd_header_size(device->connection);
4180 4181 4182 4183 4184 4185
	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;
P
Philipp Reisner 已提交
4186 4187 4188 4189 4190 4191 4192 4193 4194 4195 4196 4197 4198 4199 4200 4201 4202 4203 4204 4205 4206 4207 4208 4209 4210 4211 4212 4213 4214 4215 4216 4217 4218

	/* 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;
	dev_info(DEV, "%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. */
4219
static int receive_bitmap(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
4220
{
4221
	struct drbd_device *device;
P
Philipp Reisner 已提交
4222
	struct bm_xfer_ctx c;
4223
	int err;
4224

4225
	device = vnr_to_device(connection, pi->vnr);
4226
	if (!device)
4227
		return -EIO;
P
Philipp Reisner 已提交
4228

4229
	drbd_bm_lock(device, "receive bitmap", BM_LOCKED_SET_ALLOWED);
4230 4231
	/* you are supposed to send additional out-of-sync information
	 * if you actually set bits during this phase */
P
Philipp Reisner 已提交
4232 4233

	c = (struct bm_xfer_ctx) {
4234 4235
		.bm_bits = drbd_bm_bits(device),
		.bm_words = drbd_bm_words(device),
P
Philipp Reisner 已提交
4236 4237
	};

4238
	for(;;) {
4239
		if (pi->cmd == P_BITMAP)
4240
			err = receive_bitmap_plain(device, pi->size, pi->data, &c);
4241
		else if (pi->cmd == P_COMPRESSED_BITMAP) {
P
Philipp Reisner 已提交
4242 4243
			/* MAYBE: sanity check that we speak proto >= 90,
			 * and the feature is enabled! */
4244
			struct p_compressed_bm *p = pi->data;
P
Philipp Reisner 已提交
4245

4246
			if (pi->size > DRBD_SOCKET_BUFFER_SIZE - drbd_header_size(connection)) {
P
Philipp Reisner 已提交
4247
				dev_err(DEV, "ReportCBitmap packet too large\n");
4248
				err = -EIO;
P
Philipp Reisner 已提交
4249 4250
				goto out;
			}
4251
			if (pi->size <= sizeof(*p)) {
4252
				dev_err(DEV, "ReportCBitmap packet too small (l:%u)\n", pi->size);
4253
				err = -EIO;
4254
				goto out;
P
Philipp Reisner 已提交
4255
			}
4256
			err = drbd_recv_all(device->connection, p, pi->size);
4257 4258
			if (err)
			       goto out;
4259
			err = decode_bitmap_c(device, p, &c, pi->size);
P
Philipp Reisner 已提交
4260
		} else {
4261
			dev_warn(DEV, "receive_bitmap: cmd neither ReportBitMap nor ReportCBitMap (is 0x%x)", pi->cmd);
4262
			err = -EIO;
P
Philipp Reisner 已提交
4263 4264 4265
			goto out;
		}

4266
		c.packets[pi->cmd == P_BITMAP]++;
4267
		c.bytes[pi->cmd == P_BITMAP] += drbd_header_size(connection) + pi->size;
P
Philipp Reisner 已提交
4268

4269 4270 4271
		if (err <= 0) {
			if (err < 0)
				goto out;
P
Philipp Reisner 已提交
4272
			break;
4273
		}
4274
		err = drbd_recv_header(device->connection, pi);
4275
		if (err)
P
Philipp Reisner 已提交
4276
			goto out;
4277
	}
P
Philipp Reisner 已提交
4278

4279
	INFO_bm_xfer_stats(device, "receive", &c);
P
Philipp Reisner 已提交
4280

4281
	if (device->state.conn == C_WF_BITMAP_T) {
4282 4283
		enum drbd_state_rv rv;

4284
		err = drbd_send_bitmap(device);
4285
		if (err)
P
Philipp Reisner 已提交
4286 4287
			goto out;
		/* Omit CS_ORDERED with this state transition to avoid deadlocks. */
4288
		rv = _drbd_request_state(device, NS(conn, C_WF_SYNC_UUID), CS_VERBOSE);
4289
		D_ASSERT(rv == SS_SUCCESS);
4290
	} else if (device->state.conn != C_WF_BITMAP_S) {
P
Philipp Reisner 已提交
4291 4292 4293
		/* admin may have requested C_DISCONNECTING,
		 * other threads may have noticed network errors */
		dev_info(DEV, "unexpected cstate (%s) in receive_bitmap\n",
4294
		    drbd_conn_str(device->state.conn));
P
Philipp Reisner 已提交
4295
	}
4296
	err = 0;
P
Philipp Reisner 已提交
4297 4298

 out:
4299 4300 4301
	drbd_bm_unlock(device);
	if (!err && device->state.conn == C_WF_BITMAP_S)
		drbd_start_resync(device, C_SYNC_SOURCE);
4302
	return err;
P
Philipp Reisner 已提交
4303 4304
}

4305
static int receive_skip(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
4306
{
4307
	conn_warn(connection, "skipping unknown optional packet type %d, l: %d!\n",
4308
		 pi->cmd, pi->size);
P
Philipp Reisner 已提交
4309

4310
	return ignore_remaining_packet(connection, pi);
P
Philipp Reisner 已提交
4311 4312
}

4313
static int receive_UnplugRemote(struct drbd_connection *connection, struct packet_info *pi)
4314
{
4315 4316
	/* Make sure we've acked all the TCP data associated
	 * with the data requests being unplugged */
4317
	drbd_tcp_quickack(connection->data.socket);
4318

4319
	return 0;
4320 4321
}

4322
static int receive_out_of_sync(struct drbd_connection *connection, struct packet_info *pi)
4323
{
4324
	struct drbd_device *device;
4325
	struct p_block_desc *p = pi->data;
4326

4327
	device = vnr_to_device(connection, pi->vnr);
4328
	if (!device)
4329
		return -EIO;
4330

4331
	switch (device->state.conn) {
4332 4333 4334 4335 4336 4337
	case C_WF_SYNC_UUID:
	case C_WF_BITMAP_T:
	case C_BEHIND:
			break;
	default:
		dev_err(DEV, "ASSERT FAILED cstate = %s, expected: WFSyncUUID|WFBitMapT|Behind\n",
4338
				drbd_conn_str(device->state.conn));
4339 4340
	}

4341
	drbd_set_out_of_sync(device, be64_to_cpu(p->sector), be32_to_cpu(p->blksize));
4342

4343
	return 0;
4344 4345
}

4346 4347 4348
struct data_cmd {
	int expect_payload;
	size_t pkt_size;
4349
	int (*fn)(struct drbd_connection *, struct packet_info *);
4350 4351 4352 4353 4354 4355 4356
};

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 } ,
4357 4358 4359
	[P_BITMAP]	    = { 1, 0, receive_bitmap } ,
	[P_COMPRESSED_BITMAP] = { 1, 0, receive_bitmap } ,
	[P_UNPLUG_REMOTE]   = { 0, 0, receive_UnplugRemote },
4360 4361
	[P_DATA_REQUEST]    = { 0, sizeof(struct p_block_req), receive_DataRequest },
	[P_RS_DATA_REQUEST] = { 0, sizeof(struct p_block_req), receive_DataRequest },
4362 4363
	[P_SYNC_PARAM]	    = { 1, 0, receive_SyncParam },
	[P_SYNC_PARAM89]    = { 1, 0, receive_SyncParam },
4364 4365 4366 4367 4368 4369 4370 4371 4372 4373
	[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 },
4374
	[P_OUT_OF_SYNC]     = { 0, sizeof(struct p_block_desc), receive_out_of_sync },
4375
	[P_CONN_ST_CHG_REQ] = { 0, sizeof(struct p_req_state), receive_req_conn_state },
4376
	[P_PROTOCOL_UPDATE] = { 1, sizeof(struct p_protocol), receive_protocol },
P
Philipp Reisner 已提交
4377 4378
};

4379
static void drbdd(struct drbd_connection *connection)
P
Philipp Reisner 已提交
4380
{
4381
	struct packet_info pi;
4382
	size_t shs; /* sub header size */
4383
	int err;
P
Philipp Reisner 已提交
4384

4385
	while (get_t_state(&connection->receiver) == RUNNING) {
4386
		struct data_cmd *cmd;
P
Philipp Reisner 已提交
4387

4388 4389
		drbd_thread_current_set_cpu(&connection->receiver);
		if (drbd_recv_header(connection, &pi))
4390
			goto err_out;
P
Philipp Reisner 已提交
4391

4392
		cmd = &drbd_cmd_handler[pi.cmd];
4393
		if (unlikely(pi.cmd >= ARRAY_SIZE(drbd_cmd_handler) || !cmd->fn)) {
4394
			conn_err(connection, "Unexpected data packet %s (0x%04x)",
4395
				 cmdname(pi.cmd), pi.cmd);
4396
			goto err_out;
4397
		}
P
Philipp Reisner 已提交
4398

4399 4400
		shs = cmd->pkt_size;
		if (pi.size > shs && !cmd->expect_payload) {
4401
			conn_err(connection, "No payload expected %s l:%d\n",
4402
				 cmdname(pi.cmd), pi.size);
4403
			goto err_out;
P
Philipp Reisner 已提交
4404 4405
		}

4406
		if (shs) {
4407
			err = drbd_recv_all_warn(connection, pi.data, shs);
4408
			if (err)
4409
				goto err_out;
4410
			pi.size -= shs;
4411 4412
		}

4413
		err = cmd->fn(connection, &pi);
4414
		if (err) {
4415
			conn_err(connection, "error receiving %s, e: %d l: %d!\n",
4416
				 cmdname(pi.cmd), err, pi.size);
4417
			goto err_out;
P
Philipp Reisner 已提交
4418 4419
		}
	}
4420
	return;
P
Philipp Reisner 已提交
4421

4422
    err_out:
4423
	conn_request_state(connection, NS(conn, C_PROTOCOL_ERROR), CS_HARD);
P
Philipp Reisner 已提交
4424 4425
}

4426
void conn_flush_workqueue(struct drbd_connection *connection)
P
Philipp Reisner 已提交
4427 4428 4429 4430
{
	struct drbd_wq_barrier barr;

	barr.w.cb = w_prev_work_done;
4431
	barr.w.connection = connection;
P
Philipp Reisner 已提交
4432
	init_completion(&barr.done);
4433
	drbd_queue_work(&connection->sender_work, &barr.w);
P
Philipp Reisner 已提交
4434 4435 4436
	wait_for_completion(&barr.done);
}

4437
static void conn_disconnect(struct drbd_connection *connection)
P
Philipp Reisner 已提交
4438
{
4439
	struct drbd_device *device;
4440
	enum drbd_conns oc;
P
Philipp Reisner 已提交
4441
	int vnr;
P
Philipp Reisner 已提交
4442

4443
	if (connection->cstate == C_STANDALONE)
P
Philipp Reisner 已提交
4444 4445
		return;

4446 4447 4448 4449 4450
	/* 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.
	 */
4451
	conn_request_state(connection, NS(conn, C_NETWORK_FAILURE), CS_HARD);
4452

P
Philipp Reisner 已提交
4453
	/* asender does not clean up anything. it must not interfere, either */
4454 4455
	drbd_thread_stop(&connection->asender);
	drbd_free_sock(connection);
4456

P
Philipp Reisner 已提交
4457
	rcu_read_lock();
4458
	idr_for_each_entry(&connection->volumes, device, vnr) {
4459
		kref_get(&device->kref);
P
Philipp Reisner 已提交
4460
		rcu_read_unlock();
4461 4462
		drbd_disconnected(device);
		kref_put(&device->kref, &drbd_minor_destroy);
P
Philipp Reisner 已提交
4463 4464 4465 4466
		rcu_read_lock();
	}
	rcu_read_unlock();

4467 4468
	if (!list_empty(&connection->current_epoch->list))
		conn_err(connection, "ASSERTION FAILED: connection->current_epoch->list not empty\n");
4469
	/* ok, no more ee's on the fly, it is safe to reset the epoch_size */
4470 4471
	atomic_set(&connection->current_epoch->epoch_size, 0);
	connection->send.seen_any_write_yet = false;
4472

4473
	conn_info(connection, "Connection closed\n");
4474

4475 4476
	if (conn_highest_role(connection) == R_PRIMARY && conn_highest_pdsk(connection) >= D_UNKNOWN)
		conn_try_outdate_peer_async(connection);
4477

4478 4479
	spin_lock_irq(&connection->req_lock);
	oc = connection->cstate;
4480
	if (oc >= C_UNCONNECTED)
4481
		_conn_request_state(connection, NS(conn, C_UNCONNECTED), CS_VERBOSE);
4482

4483
	spin_unlock_irq(&connection->req_lock);
4484

4485
	if (oc == C_DISCONNECTING)
4486
		conn_request_state(connection, NS(conn, C_STANDALONE), CS_VERBOSE | CS_HARD);
4487 4488
}

4489
static int drbd_disconnected(struct drbd_device *device)
4490 4491
{
	unsigned int i;
P
Philipp Reisner 已提交
4492

4493
	/* wait for current activity to cease. */
4494
	spin_lock_irq(&device->connection->req_lock);
4495 4496 4497
	_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);
4498
	spin_unlock_irq(&device->connection->req_lock);
P
Philipp Reisner 已提交
4499 4500 4501 4502 4503 4504 4505 4506 4507 4508 4509

	/* 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. */
4510 4511 4512 4513 4514
	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);
P
Philipp Reisner 已提交
4515

4516 4517
	del_timer_sync(&device->resync_timer);
	resync_timer_fn((unsigned long)device);
P
Philipp Reisner 已提交
4518 4519 4520 4521

	/* 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" */
4522
	drbd_flush_workqueue(device);
P
Philipp Reisner 已提交
4523

4524
	drbd_finish_peer_reqs(device);
P
Philipp Reisner 已提交
4525

4526 4527 4528
	/* 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(). */
4529
	drbd_flush_workqueue(device);
4530

4531 4532
	/* need to do it again, drbd_finish_peer_reqs() may have populated it
	 * again via drbd_try_clear_on_disk_bm(). */
4533
	drbd_rs_cancel_all(device);
P
Philipp Reisner 已提交
4534

4535 4536
	kfree(device->p_uuid);
	device->p_uuid = NULL;
P
Philipp Reisner 已提交
4537

4538
	if (!drbd_suspended(device))
4539
		tl_clear(device->connection);
P
Philipp Reisner 已提交
4540

4541
	drbd_md_sync(device);
P
Philipp Reisner 已提交
4542

4543 4544
	/* serialize with bitmap writeout triggered by the state change,
	 * if any. */
4545
	wait_event(device->misc_wait, !test_bit(BITMAP_IO, &device->flags));
4546

P
Philipp Reisner 已提交
4547 4548 4549 4550 4551 4552 4553
	/* 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.
	 */
4554
	i = drbd_free_peer_reqs(device, &device->net_ee);
P
Philipp Reisner 已提交
4555 4556
	if (i)
		dev_info(DEV, "net_ee not empty, killed %u entries\n", i);
4557
	i = atomic_read(&device->pp_in_use_by_net);
4558 4559
	if (i)
		dev_info(DEV, "pp_in_use_by_net = %d, expected 0\n", i);
4560
	i = atomic_read(&device->pp_in_use);
P
Philipp Reisner 已提交
4561
	if (i)
4562
		dev_info(DEV, "pp_in_use = %d, expected 0\n", i);
P
Philipp Reisner 已提交
4563

4564 4565 4566 4567
	D_ASSERT(list_empty(&device->read_ee));
	D_ASSERT(list_empty(&device->active_ee));
	D_ASSERT(list_empty(&device->sync_ee));
	D_ASSERT(list_empty(&device->done_ee));
P
Philipp Reisner 已提交
4568

4569
	return 0;
P
Philipp Reisner 已提交
4570 4571 4572 4573 4574 4575 4576 4577 4578 4579 4580
}

/*
 * 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.
 */
4581
static int drbd_send_features(struct drbd_connection *connection)
P
Philipp Reisner 已提交
4582
{
4583 4584
	struct drbd_socket *sock;
	struct p_connection_features *p;
P
Philipp Reisner 已提交
4585

4586 4587
	sock = &connection->data;
	p = conn_prepare_command(connection, sock);
4588
	if (!p)
4589
		return -EIO;
P
Philipp Reisner 已提交
4590 4591 4592
	memset(p, 0, sizeof(*p));
	p->protocol_min = cpu_to_be32(PRO_VERSION_MIN);
	p->protocol_max = cpu_to_be32(PRO_VERSION_MAX);
4593
	return conn_send_command(connection, sock, P_CONNECTION_FEATURES, sizeof(*p), NULL, 0);
P
Philipp Reisner 已提交
4594 4595 4596 4597 4598 4599 4600 4601 4602
}

/*
 * 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.
 */
4603
static int drbd_do_features(struct drbd_connection *connection)
P
Philipp Reisner 已提交
4604
{
4605
	/* ASSERT current == connection->receiver ... */
4606 4607
	struct p_connection_features *p;
	const int expect = sizeof(struct p_connection_features);
4608
	struct packet_info pi;
4609
	int err;
P
Philipp Reisner 已提交
4610

4611
	err = drbd_send_features(connection);
4612
	if (err)
P
Philipp Reisner 已提交
4613 4614
		return 0;

4615
	err = drbd_recv_header(connection, &pi);
4616
	if (err)
P
Philipp Reisner 已提交
4617 4618
		return 0;

4619
	if (pi.cmd != P_CONNECTION_FEATURES) {
4620
		conn_err(connection, "expected ConnectionFeatures packet, received: %s (0x%04x)\n",
4621
			 cmdname(pi.cmd), pi.cmd);
P
Philipp Reisner 已提交
4622 4623 4624
		return -1;
	}

4625
	if (pi.size != expect) {
4626
		conn_err(connection, "expected ConnectionFeatures length: %u, received: %u\n",
4627
		     expect, pi.size);
P
Philipp Reisner 已提交
4628 4629 4630
		return -1;
	}

4631
	p = pi.data;
4632
	err = drbd_recv_all_warn(connection, p, expect);
4633
	if (err)
P
Philipp Reisner 已提交
4634 4635 4636 4637 4638 4639 4640 4641 4642 4643 4644
		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;

4645
	connection->agreed_pro_version = min_t(int, PRO_VERSION_MAX, p->protocol_max);
P
Philipp Reisner 已提交
4646

4647 4648
	conn_info(connection, "Handshake successful: "
	     "Agreed network protocol version %d\n", connection->agreed_pro_version);
P
Philipp Reisner 已提交
4649 4650 4651 4652

	return 1;

 incompat:
4653
	conn_err(connection, "incompatible DRBD dialects: "
P
Philipp Reisner 已提交
4654 4655 4656 4657 4658 4659 4660
	    "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)
4661
static int drbd_do_auth(struct drbd_connection *connection)
P
Philipp Reisner 已提交
4662
{
4663 4664
	conn_err(connection, "This kernel was build without CONFIG_CRYPTO_HMAC.\n");
	conn_err(connection, "You need to disable 'cram-hmac-alg' in drbd.conf.\n");
4665
	return -1;
P
Philipp Reisner 已提交
4666 4667 4668
}
#else
#define CHALLENGE_LEN 64
4669 4670 4671 4672 4673 4674 4675

/* Return value:
	1 - auth succeeded,
	0 - failed, try again (network error),
	-1 - auth failed, don't try again.
*/

4676
static int drbd_do_auth(struct drbd_connection *connection)
P
Philipp Reisner 已提交
4677
{
4678
	struct drbd_socket *sock;
P
Philipp Reisner 已提交
4679 4680 4681 4682 4683
	char my_challenge[CHALLENGE_LEN];  /* 64 Bytes... */
	struct scatterlist sg;
	char *response = NULL;
	char *right_response = NULL;
	char *peers_ch = NULL;
4684 4685
	unsigned int key_len;
	char secret[SHARED_SECRET_MAX]; /* 64 byte */
P
Philipp Reisner 已提交
4686 4687
	unsigned int resp_size;
	struct hash_desc desc;
4688
	struct packet_info pi;
4689
	struct net_conf *nc;
4690
	int err, rv;
P
Philipp Reisner 已提交
4691

4692
	/* FIXME: Put the challenge/response into the preallocated socket buffer.  */
P
Philipp Reisner 已提交
4693

4694
	rcu_read_lock();
4695
	nc = rcu_dereference(connection->net_conf);
4696 4697 4698 4699
	key_len = strlen(nc->shared_secret);
	memcpy(secret, nc->shared_secret, key_len);
	rcu_read_unlock();

4700
	desc.tfm = connection->cram_hmac_tfm;
P
Philipp Reisner 已提交
4701 4702
	desc.flags = 0;

4703
	rv = crypto_hash_setkey(connection->cram_hmac_tfm, (u8 *)secret, key_len);
P
Philipp Reisner 已提交
4704
	if (rv) {
4705
		conn_err(connection, "crypto_hash_setkey() failed with %d\n", rv);
4706
		rv = -1;
P
Philipp Reisner 已提交
4707 4708 4709 4710 4711
		goto fail;
	}

	get_random_bytes(my_challenge, CHALLENGE_LEN);

4712 4713
	sock = &connection->data;
	if (!conn_prepare_command(connection, sock)) {
4714 4715 4716
		rv = 0;
		goto fail;
	}
4717
	rv = !conn_send_command(connection, sock, P_AUTH_CHALLENGE, 0,
4718
				my_challenge, CHALLENGE_LEN);
P
Philipp Reisner 已提交
4719 4720 4721
	if (!rv)
		goto fail;

4722
	err = drbd_recv_header(connection, &pi);
4723 4724
	if (err) {
		rv = 0;
P
Philipp Reisner 已提交
4725
		goto fail;
4726
	}
P
Philipp Reisner 已提交
4727

4728
	if (pi.cmd != P_AUTH_CHALLENGE) {
4729
		conn_err(connection, "expected AuthChallenge packet, received: %s (0x%04x)\n",
4730
			 cmdname(pi.cmd), pi.cmd);
P
Philipp Reisner 已提交
4731 4732 4733 4734
		rv = 0;
		goto fail;
	}

4735
	if (pi.size > CHALLENGE_LEN * 2) {
4736
		conn_err(connection, "expected AuthChallenge payload too big.\n");
4737
		rv = -1;
P
Philipp Reisner 已提交
4738 4739 4740
		goto fail;
	}

4741
	peers_ch = kmalloc(pi.size, GFP_NOIO);
P
Philipp Reisner 已提交
4742
	if (peers_ch == NULL) {
4743
		conn_err(connection, "kmalloc of peers_ch failed\n");
4744
		rv = -1;
P
Philipp Reisner 已提交
4745 4746 4747
		goto fail;
	}

4748
	err = drbd_recv_all_warn(connection, peers_ch, pi.size);
4749
	if (err) {
P
Philipp Reisner 已提交
4750 4751 4752 4753
		rv = 0;
		goto fail;
	}

4754
	resp_size = crypto_hash_digestsize(connection->cram_hmac_tfm);
P
Philipp Reisner 已提交
4755 4756
	response = kmalloc(resp_size, GFP_NOIO);
	if (response == NULL) {
4757
		conn_err(connection, "kmalloc of response failed\n");
4758
		rv = -1;
P
Philipp Reisner 已提交
4759 4760 4761 4762
		goto fail;
	}

	sg_init_table(&sg, 1);
4763
	sg_set_buf(&sg, peers_ch, pi.size);
P
Philipp Reisner 已提交
4764 4765 4766

	rv = crypto_hash_digest(&desc, &sg, sg.length, response);
	if (rv) {
4767
		conn_err(connection, "crypto_hash_digest() failed with %d\n", rv);
4768
		rv = -1;
P
Philipp Reisner 已提交
4769 4770 4771
		goto fail;
	}

4772
	if (!conn_prepare_command(connection, sock)) {
4773
		rv = 0;
P
Philipp Reisner 已提交
4774
		goto fail;
4775
	}
4776
	rv = !conn_send_command(connection, sock, P_AUTH_RESPONSE, 0,
4777
				response, resp_size);
P
Philipp Reisner 已提交
4778 4779 4780
	if (!rv)
		goto fail;

4781
	err = drbd_recv_header(connection, &pi);
4782
	if (err) {
P
Philipp Reisner 已提交
4783 4784 4785 4786
		rv = 0;
		goto fail;
	}

4787
	if (pi.cmd != P_AUTH_RESPONSE) {
4788
		conn_err(connection, "expected AuthResponse packet, received: %s (0x%04x)\n",
4789
			 cmdname(pi.cmd), pi.cmd);
P
Philipp Reisner 已提交
4790 4791 4792 4793
		rv = 0;
		goto fail;
	}

4794
	if (pi.size != resp_size) {
4795
		conn_err(connection, "expected AuthResponse payload of wrong size\n");
P
Philipp Reisner 已提交
4796 4797 4798 4799
		rv = 0;
		goto fail;
	}

4800
	err = drbd_recv_all_warn(connection, response , resp_size);
4801
	if (err) {
P
Philipp Reisner 已提交
4802 4803 4804 4805 4806
		rv = 0;
		goto fail;
	}

	right_response = kmalloc(resp_size, GFP_NOIO);
4807
	if (right_response == NULL) {
4808
		conn_err(connection, "kmalloc of right_response failed\n");
4809
		rv = -1;
P
Philipp Reisner 已提交
4810 4811 4812 4813 4814 4815 4816
		goto fail;
	}

	sg_set_buf(&sg, my_challenge, CHALLENGE_LEN);

	rv = crypto_hash_digest(&desc, &sg, sg.length, right_response);
	if (rv) {
4817
		conn_err(connection, "crypto_hash_digest() failed with %d\n", rv);
4818
		rv = -1;
P
Philipp Reisner 已提交
4819 4820 4821 4822 4823 4824
		goto fail;
	}

	rv = !memcmp(response, right_response, resp_size);

	if (rv)
4825
		conn_info(connection, "Peer authenticated using %d bytes HMAC\n",
4826
		     resp_size);
4827 4828
	else
		rv = -1;
P
Philipp Reisner 已提交
4829 4830 4831 4832 4833 4834 4835 4836 4837 4838 4839 4840

 fail:
	kfree(peers_ch);
	kfree(response);
	kfree(right_response);

	return rv;
}
#endif

int drbdd_init(struct drbd_thread *thi)
{
4841
	struct drbd_connection *connection = thi->connection;
P
Philipp Reisner 已提交
4842 4843
	int h;

4844
	conn_info(connection, "receiver (re)started\n");
P
Philipp Reisner 已提交
4845 4846

	do {
4847
		h = conn_connect(connection);
P
Philipp Reisner 已提交
4848
		if (h == 0) {
4849
			conn_disconnect(connection);
4850
			schedule_timeout_interruptible(HZ);
P
Philipp Reisner 已提交
4851 4852
		}
		if (h == -1) {
4853 4854
			conn_warn(connection, "Discarding network configuration.\n");
			conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_HARD);
P
Philipp Reisner 已提交
4855 4856 4857
		}
	} while (h == 0);

4858
	if (h > 0)
4859
		drbdd(connection);
P
Philipp Reisner 已提交
4860

4861
	conn_disconnect(connection);
P
Philipp Reisner 已提交
4862

4863
	conn_info(connection, "receiver terminated\n");
P
Philipp Reisner 已提交
4864 4865 4866 4867 4868
	return 0;
}

/* ********* acknowledge sender ******** */

4869
static int got_conn_RqSReply(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
4870
{
4871
	struct p_req_state_reply *p = pi->data;
4872 4873 4874
	int retcode = be32_to_cpu(p->retcode);

	if (retcode >= SS_SUCCESS) {
4875
		set_bit(CONN_WD_ST_CHG_OKAY, &connection->flags);
4876
	} else {
4877 4878
		set_bit(CONN_WD_ST_CHG_FAIL, &connection->flags);
		conn_err(connection, "Requested state change failed by peer: %s (%d)\n",
4879 4880
			 drbd_set_st_err_str(retcode), retcode);
	}
4881
	wake_up(&connection->ping_wait);
4882

4883
	return 0;
4884
}
P
Philipp Reisner 已提交
4885

4886
static int got_RqSReply(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
4887
{
4888
	struct drbd_device *device;
4889
	struct p_req_state_reply *p = pi->data;
P
Philipp Reisner 已提交
4890 4891
	int retcode = be32_to_cpu(p->retcode);

4892
	device = vnr_to_device(connection, pi->vnr);
4893
	if (!device)
4894
		return -EIO;
4895

4896 4897 4898
	if (test_bit(CONN_WD_ST_CHG_REQ, &connection->flags)) {
		D_ASSERT(connection->agreed_pro_version < 100);
		return got_conn_RqSReply(connection, pi);
4899 4900
	}

P
Philipp Reisner 已提交
4901
	if (retcode >= SS_SUCCESS) {
4902
		set_bit(CL_ST_CHG_SUCCESS, &device->flags);
P
Philipp Reisner 已提交
4903
	} else {
4904
		set_bit(CL_ST_CHG_FAIL, &device->flags);
P
Philipp Reisner 已提交
4905
		dev_err(DEV, "Requested state change failed by peer: %s (%d)\n",
4906
			drbd_set_st_err_str(retcode), retcode);
P
Philipp Reisner 已提交
4907
	}
4908
	wake_up(&device->state_wait);
P
Philipp Reisner 已提交
4909

4910
	return 0;
P
Philipp Reisner 已提交
4911 4912
}

4913
static int got_Ping(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
4914
{
4915
	return drbd_send_ping_ack(connection);
P
Philipp Reisner 已提交
4916 4917 4918

}

4919
static int got_PingAck(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
4920 4921
{
	/* restore idle timeout */
4922 4923 4924
	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);
P
Philipp Reisner 已提交
4925

4926
	return 0;
P
Philipp Reisner 已提交
4927 4928
}

4929
static int got_IsInSync(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
4930
{
4931
	struct drbd_device *device;
4932
	struct p_block_ack *p = pi->data;
P
Philipp Reisner 已提交
4933 4934 4935
	sector_t sector = be64_to_cpu(p->sector);
	int blksize = be32_to_cpu(p->blksize);

4936
	device = vnr_to_device(connection, pi->vnr);
4937
	if (!device)
4938
		return -EIO;
4939

4940
	D_ASSERT(device->connection->agreed_pro_version >= 89);
P
Philipp Reisner 已提交
4941

4942
	update_peer_seq(device, be32_to_cpu(p->seq_num));
P
Philipp Reisner 已提交
4943

4944 4945 4946
	if (get_ldev(device)) {
		drbd_rs_complete_io(device, sector);
		drbd_set_in_sync(device, sector, blksize);
4947
		/* rs_same_csums is supposed to count in units of BM_BLOCK_SIZE */
4948 4949
		device->rs_same_csum += (blksize >> BM_BLOCK_SHIFT);
		put_ldev(device);
4950
	}
4951 4952
	dec_rs_pending(device);
	atomic_add(blksize >> 9, &device->rs_sect_in);
P
Philipp Reisner 已提交
4953

4954
	return 0;
P
Philipp Reisner 已提交
4955 4956
}

4957
static int
4958
validate_req_change_req_state(struct drbd_device *device, u64 id, sector_t sector,
4959 4960
			      struct rb_root *root, const char *func,
			      enum drbd_req_event what, bool missing_ok)
P
Philipp Reisner 已提交
4961 4962 4963 4964
{
	struct drbd_request *req;
	struct bio_and_error m;

4965
	spin_lock_irq(&device->connection->req_lock);
4966
	req = find_request(device, root, id, sector, missing_ok, func);
P
Philipp Reisner 已提交
4967
	if (unlikely(!req)) {
4968
		spin_unlock_irq(&device->connection->req_lock);
4969
		return -EIO;
P
Philipp Reisner 已提交
4970 4971
	}
	__req_mod(req, what, &m);
4972
	spin_unlock_irq(&device->connection->req_lock);
P
Philipp Reisner 已提交
4973 4974

	if (m.bio)
4975
		complete_master_bio(device, &m);
4976
	return 0;
P
Philipp Reisner 已提交
4977 4978
}

4979
static int got_BlockAck(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
4980
{
4981
	struct drbd_device *device;
4982
	struct p_block_ack *p = pi->data;
P
Philipp Reisner 已提交
4983 4984 4985 4986
	sector_t sector = be64_to_cpu(p->sector);
	int blksize = be32_to_cpu(p->blksize);
	enum drbd_req_event what;

4987
	device = vnr_to_device(connection, pi->vnr);
4988
	if (!device)
4989
		return -EIO;
4990

4991
	update_peer_seq(device, be32_to_cpu(p->seq_num));
P
Philipp Reisner 已提交
4992

4993
	if (p->block_id == ID_SYNCER) {
4994 4995
		drbd_set_in_sync(device, sector, blksize);
		dec_rs_pending(device);
4996
		return 0;
P
Philipp Reisner 已提交
4997
	}
4998
	switch (pi->cmd) {
P
Philipp Reisner 已提交
4999
	case P_RS_WRITE_ACK:
5000
		what = WRITE_ACKED_BY_PEER_AND_SIS;
P
Philipp Reisner 已提交
5001 5002
		break;
	case P_WRITE_ACK:
5003
		what = WRITE_ACKED_BY_PEER;
P
Philipp Reisner 已提交
5004 5005
		break;
	case P_RECV_ACK:
5006
		what = RECV_ACKED_BY_PEER;
P
Philipp Reisner 已提交
5007
		break;
5008 5009
	case P_SUPERSEDED:
		what = CONFLICT_RESOLVED;
P
Philipp Reisner 已提交
5010
		break;
5011 5012
	case P_RETRY_WRITE:
		what = POSTPONE_WRITE;
P
Philipp Reisner 已提交
5013 5014
		break;
	default:
5015
		BUG();
P
Philipp Reisner 已提交
5016 5017
	}

5018 5019
	return validate_req_change_req_state(device, p->block_id, sector,
					     &device->write_requests, __func__,
5020
					     what, false);
P
Philipp Reisner 已提交
5021 5022
}

5023
static int got_NegAck(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
5024
{
5025
	struct drbd_device *device;
5026
	struct p_block_ack *p = pi->data;
P
Philipp Reisner 已提交
5027
	sector_t sector = be64_to_cpu(p->sector);
5028
	int size = be32_to_cpu(p->blksize);
5029
	int err;
P
Philipp Reisner 已提交
5030

5031
	device = vnr_to_device(connection, pi->vnr);
5032
	if (!device)
5033
		return -EIO;
P
Philipp Reisner 已提交
5034

5035
	update_peer_seq(device, be32_to_cpu(p->seq_num));
P
Philipp Reisner 已提交
5036

5037
	if (p->block_id == ID_SYNCER) {
5038 5039
		dec_rs_pending(device);
		drbd_rs_failed_io(device, sector, size);
5040
		return 0;
P
Philipp Reisner 已提交
5041
	}
5042

5043 5044
	err = validate_req_change_req_state(device, p->block_id, sector,
					    &device->write_requests, __func__,
5045
					    NEG_ACKED, true);
5046
	if (err) {
5047 5048 5049 5050 5051
		/* 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. */
5052
		drbd_set_out_of_sync(device, sector, size);
5053
	}
5054
	return 0;
P
Philipp Reisner 已提交
5055 5056
}

5057
static int got_NegDReply(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
5058
{
5059
	struct drbd_device *device;
5060
	struct p_block_ack *p = pi->data;
P
Philipp Reisner 已提交
5061 5062
	sector_t sector = be64_to_cpu(p->sector);

5063
	device = vnr_to_device(connection, pi->vnr);
5064
	if (!device)
5065
		return -EIO;
5066

5067
	update_peer_seq(device, be32_to_cpu(p->seq_num));
5068

5069
	dev_err(DEV, "Got NegDReply; Sector %llus, len %u.\n",
P
Philipp Reisner 已提交
5070 5071
	    (unsigned long long)sector, be32_to_cpu(p->blksize));

5072 5073
	return validate_req_change_req_state(device, p->block_id, sector,
					     &device->read_requests, __func__,
5074
					     NEG_ACKED, false);
P
Philipp Reisner 已提交
5075 5076
}

5077
static int got_NegRSDReply(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
5078
{
5079
	struct drbd_device *device;
P
Philipp Reisner 已提交
5080 5081
	sector_t sector;
	int size;
5082
	struct p_block_ack *p = pi->data;
5083

5084
	device = vnr_to_device(connection, pi->vnr);
5085
	if (!device)
5086
		return -EIO;
P
Philipp Reisner 已提交
5087 5088 5089 5090

	sector = be64_to_cpu(p->sector);
	size = be32_to_cpu(p->blksize);

5091
	update_peer_seq(device, be32_to_cpu(p->seq_num));
P
Philipp Reisner 已提交
5092

5093
	dec_rs_pending(device);
P
Philipp Reisner 已提交
5094

5095 5096
	if (get_ldev_if_state(device, D_FAILED)) {
		drbd_rs_complete_io(device, sector);
5097
		switch (pi->cmd) {
5098
		case P_NEG_RS_DREPLY:
5099
			drbd_rs_failed_io(device, sector, size);
5100 5101 5102
		case P_RS_CANCEL:
			break;
		default:
5103
			BUG();
5104
		}
5105
		put_ldev(device);
P
Philipp Reisner 已提交
5106 5107
	}

5108
	return 0;
P
Philipp Reisner 已提交
5109 5110
}

5111
static int got_BarrierAck(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
5112
{
5113
	struct p_barrier_ack *p = pi->data;
5114
	struct drbd_device *device;
5115
	int vnr;
5116

5117
	tl_release(connection, p->barrier, be32_to_cpu(p->set_size));
P
Philipp Reisner 已提交
5118

5119
	rcu_read_lock();
5120
	idr_for_each_entry(&connection->volumes, device, vnr) {
5121 5122 5123 5124 5125
		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);
5126
		}
5127
	}
5128
	rcu_read_unlock();
5129

5130
	return 0;
P
Philipp Reisner 已提交
5131 5132
}

5133
static int got_OVResult(struct drbd_connection *connection, struct packet_info *pi)
P
Philipp Reisner 已提交
5134
{
5135
	struct drbd_device *device;
5136
	struct p_block_ack *p = pi->data;
P
Philipp Reisner 已提交
5137 5138 5139 5140
	struct drbd_work *w;
	sector_t sector;
	int size;

5141
	device = vnr_to_device(connection, pi->vnr);
5142
	if (!device)
5143
		return -EIO;
5144

P
Philipp Reisner 已提交
5145 5146 5147
	sector = be64_to_cpu(p->sector);
	size = be32_to_cpu(p->blksize);

5148
	update_peer_seq(device, be32_to_cpu(p->seq_num));
P
Philipp Reisner 已提交
5149 5150

	if (be64_to_cpu(p->block_id) == ID_OUT_OF_SYNC)
5151
		drbd_ov_out_of_sync_found(device, sector, size);
P
Philipp Reisner 已提交
5152
	else
5153
		ov_out_of_sync_print(device);
P
Philipp Reisner 已提交
5154

5155
	if (!get_ldev(device))
5156
		return 0;
5157

5158 5159
	drbd_rs_complete_io(device, sector);
	dec_rs_pending(device);
P
Philipp Reisner 已提交
5160

5161
	--device->ov_left;
5162 5163

	/* let's advance progress step marks only for every other megabyte */
5164 5165
	if ((device->ov_left & 0x200) == 0x200)
		drbd_advance_rs_marks(device, device->ov_left);
5166

5167
	if (device->ov_left == 0) {
P
Philipp Reisner 已提交
5168 5169 5170
		w = kmalloc(sizeof(*w), GFP_NOIO);
		if (w) {
			w->cb = w_ov_finished;
5171
			w->device = device;
5172
			drbd_queue_work(&device->connection->sender_work, w);
P
Philipp Reisner 已提交
5173 5174
		} else {
			dev_err(DEV, "kmalloc(w) failed.");
5175 5176
			ov_out_of_sync_print(device);
			drbd_resync_finished(device);
P
Philipp Reisner 已提交
5177 5178
		}
	}
5179
	put_ldev(device);
5180
	return 0;
P
Philipp Reisner 已提交
5181 5182
}

5183
static int got_skip(struct drbd_connection *connection, struct packet_info *pi)
5184
{
5185
	return 0;
P
Philipp Reisner 已提交
5186 5187
}

5188
static int connection_finish_peer_reqs(struct drbd_connection *connection)
5189
{
5190
	struct drbd_device *device;
P
Philipp Reisner 已提交
5191
	int vnr, not_empty = 0;
5192 5193

	do {
5194
		clear_bit(SIGNAL_ASENDER, &connection->flags);
5195
		flush_signals(current);
P
Philipp Reisner 已提交
5196 5197

		rcu_read_lock();
5198
		idr_for_each_entry(&connection->volumes, device, vnr) {
5199
			kref_get(&device->kref);
P
Philipp Reisner 已提交
5200
			rcu_read_unlock();
5201 5202
			if (drbd_finish_peer_reqs(device)) {
				kref_put(&device->kref, &drbd_minor_destroy);
P
Philipp Reisner 已提交
5203
				return 1;
5204
			}
5205
			kref_put(&device->kref, &drbd_minor_destroy);
P
Philipp Reisner 已提交
5206
			rcu_read_lock();
5207
		}
5208
		set_bit(SIGNAL_ASENDER, &connection->flags);
5209

5210 5211
		spin_lock_irq(&connection->req_lock);
		idr_for_each_entry(&connection->volumes, device, vnr) {
5212
			not_empty = !list_empty(&device->done_ee);
5213 5214 5215
			if (not_empty)
				break;
		}
5216
		spin_unlock_irq(&connection->req_lock);
P
Philipp Reisner 已提交
5217
		rcu_read_unlock();
5218 5219 5220
	} while (not_empty);

	return 0;
5221 5222
}

P
Philipp Reisner 已提交
5223 5224
struct asender_cmd {
	size_t pkt_size;
5225
	int (*fn)(struct drbd_connection *connection, struct packet_info *);
P
Philipp Reisner 已提交
5226 5227
};

5228
static struct asender_cmd asender_tbl[] = {
5229 5230
	[P_PING]	    = { 0, got_Ping },
	[P_PING_ACK]	    = { 0, got_PingAck },
P
Philipp Reisner 已提交
5231 5232 5233
	[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 },
5234
	[P_SUPERSEDED]   = { sizeof(struct p_block_ack), got_BlockAck },
P
Philipp Reisner 已提交
5235 5236
	[P_NEG_ACK]	    = { sizeof(struct p_block_ack), got_NegAck },
	[P_NEG_DREPLY]	    = { sizeof(struct p_block_ack), got_NegDReply },
5237
	[P_NEG_RS_DREPLY]   = { sizeof(struct p_block_ack), got_NegRSDReply },
P
Philipp Reisner 已提交
5238 5239 5240 5241
	[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 },
5242
	[P_DELAY_PROBE]     = { sizeof(struct p_delay_probe93), got_skip },
5243 5244 5245
	[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 },
5246
};
P
Philipp Reisner 已提交
5247 5248 5249

int drbd_asender(struct drbd_thread *thi)
{
5250
	struct drbd_connection *connection = thi->connection;
P
Philipp Reisner 已提交
5251
	struct asender_cmd *cmd = NULL;
5252
	struct packet_info pi;
5253
	int rv;
5254
	void *buf    = connection->meta.rbuf;
P
Philipp Reisner 已提交
5255
	int received = 0;
5256
	unsigned int header_size = drbd_header_size(connection);
5257
	int expect   = header_size;
5258 5259
	bool ping_timeout_active = false;
	struct net_conf *nc;
5260
	int ping_timeo, tcp_cork, ping_int;
P
Philipp Reisner 已提交
5261
	struct sched_param param = { .sched_priority = 2 };
P
Philipp Reisner 已提交
5262

P
Philipp Reisner 已提交
5263 5264
	rv = sched_setscheduler(current, SCHED_RR, &param);
	if (rv < 0)
5265
		conn_err(connection, "drbd_asender: ERROR set priority, ret=%d\n", rv);
P
Philipp Reisner 已提交
5266

5267
	while (get_t_state(thi) == RUNNING) {
5268
		drbd_thread_current_set_cpu(thi);
P
Philipp Reisner 已提交
5269

5270
		rcu_read_lock();
5271
		nc = rcu_dereference(connection->net_conf);
5272
		ping_timeo = nc->ping_timeo;
5273
		tcp_cork = nc->tcp_cork;
5274 5275 5276
		ping_int = nc->ping_int;
		rcu_read_unlock();

5277 5278 5279
		if (test_and_clear_bit(SEND_PING, &connection->flags)) {
			if (drbd_send_ping(connection)) {
				conn_err(connection, "drbd_send_ping has failed\n");
P
Philipp Reisner 已提交
5280
				goto reconnect;
5281
			}
5282
			connection->meta.socket->sk->sk_rcvtimeo = ping_timeo * HZ / 10;
5283
			ping_timeout_active = true;
P
Philipp Reisner 已提交
5284 5285
		}

5286 5287
		/* TODO: conditionally cork; it may hurt latency if we cork without
		   much to send */
5288
		if (tcp_cork)
5289 5290 5291
			drbd_tcp_cork(connection->meta.socket);
		if (connection_finish_peer_reqs(connection)) {
			conn_err(connection, "connection_finish_peer_reqs() failed\n");
5292
			goto reconnect;
P
Philipp Reisner 已提交
5293 5294
		}
		/* but unconditionally uncork unless disabled */
5295
		if (tcp_cork)
5296
			drbd_tcp_uncork(connection->meta.socket);
P
Philipp Reisner 已提交
5297 5298 5299 5300 5301

		/* short circuit, recv_msg would return EINTR anyways. */
		if (signal_pending(current))
			continue;

5302 5303
		rv = drbd_recv_short(connection->meta.socket, buf, expect-received, 0);
		clear_bit(SIGNAL_ASENDER, &connection->flags);
P
Philipp Reisner 已提交
5304 5305 5306 5307 5308 5309 5310 5311 5312 5313 5314 5315 5316 5317 5318 5319 5320

		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"
		 */
		if (likely(rv > 0)) {
			received += rv;
			buf	 += rv;
		} else if (rv == 0) {
5321
			if (test_bit(DISCONNECT_SENT, &connection->flags)) {
5322 5323
				long t;
				rcu_read_lock();
5324
				t = rcu_dereference(connection->net_conf)->ping_timeo * HZ/10;
5325 5326
				rcu_read_unlock();

5327 5328
				t = wait_event_timeout(connection->ping_wait,
						       connection->cstate < C_WF_REPORT_PARAMS,
5329
						       t);
5330 5331 5332
				if (t)
					break;
			}
5333
			conn_err(connection, "meta connection shut down by peer.\n");
P
Philipp Reisner 已提交
5334 5335
			goto reconnect;
		} else if (rv == -EAGAIN) {
5336 5337
			/* If the data socket received something meanwhile,
			 * that is good enough: peer is still alive. */
5338 5339
			if (time_after(connection->last_received,
				jiffies - connection->meta.socket->sk->sk_rcvtimeo))
5340
				continue;
5341
			if (ping_timeout_active) {
5342
				conn_err(connection, "PingAck did not arrive in time.\n");
P
Philipp Reisner 已提交
5343 5344
				goto reconnect;
			}
5345
			set_bit(SEND_PING, &connection->flags);
P
Philipp Reisner 已提交
5346 5347 5348 5349
			continue;
		} else if (rv == -EINTR) {
			continue;
		} else {
5350
			conn_err(connection, "sock_recvmsg returned %d\n", rv);
P
Philipp Reisner 已提交
5351 5352 5353 5354
			goto reconnect;
		}

		if (received == expect && cmd == NULL) {
5355
			if (decode_header(connection, connection->meta.rbuf, &pi))
P
Philipp Reisner 已提交
5356
				goto reconnect;
5357
			cmd = &asender_tbl[pi.cmd];
5358
			if (pi.cmd >= ARRAY_SIZE(asender_tbl) || !cmd->fn) {
5359
				conn_err(connection, "Unexpected meta packet %s (0x%04x)\n",
5360
					 cmdname(pi.cmd), pi.cmd);
P
Philipp Reisner 已提交
5361 5362
				goto disconnect;
			}
5363
			expect = header_size + cmd->pkt_size;
5364
			if (pi.size != expect - header_size) {
5365
				conn_err(connection, "Wrong packet size on meta (c: %d, l: %d)\n",
5366
					pi.cmd, pi.size);
P
Philipp Reisner 已提交
5367
				goto reconnect;
5368
			}
P
Philipp Reisner 已提交
5369 5370
		}
		if (received == expect) {
5371
			bool err;
5372

5373
			err = cmd->fn(connection, &pi);
5374
			if (err) {
5375
				conn_err(connection, "%pf failed\n", cmd->fn);
P
Philipp Reisner 已提交
5376
				goto reconnect;
5377
			}
P
Philipp Reisner 已提交
5378

5379
			connection->last_received = jiffies;
5380

5381 5382
			if (cmd == &asender_tbl[P_PING_ACK]) {
				/* restore idle timeout */
5383
				connection->meta.socket->sk->sk_rcvtimeo = ping_int * HZ;
5384 5385
				ping_timeout_active = false;
			}
5386

5387
			buf	 = connection->meta.rbuf;
P
Philipp Reisner 已提交
5388
			received = 0;
5389
			expect	 = header_size;
P
Philipp Reisner 已提交
5390 5391 5392 5393 5394 5395
			cmd	 = NULL;
		}
	}

	if (0) {
reconnect:
5396 5397
		conn_request_state(connection, NS(conn, C_NETWORK_FAILURE), CS_HARD);
		conn_md_sync(connection);
P
Philipp Reisner 已提交
5398 5399 5400
	}
	if (0) {
disconnect:
5401
		conn_request_state(connection, NS(conn, C_DISCONNECTING), CS_HARD);
P
Philipp Reisner 已提交
5402
	}
5403
	clear_bit(SIGNAL_ASENDER, &connection->flags);
P
Philipp Reisner 已提交
5404

5405
	conn_info(connection, "asender terminated\n");
P
Philipp Reisner 已提交
5406 5407 5408

	return 0;
}