drbd_main.c 91.4 KB
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/*
   drbd.c

   This file is part of DRBD by Philipp Reisner and Lars Ellenberg.

   Copyright (C) 2001-2008, LINBIT Information Technologies GmbH.
   Copyright (C) 1999-2008, Philipp Reisner <philipp.reisner@linbit.com>.
   Copyright (C) 2002-2008, Lars Ellenberg <lars.ellenberg@linbit.com>.

   Thanks to Carter Burden, Bart Grantham and Gennadiy Nerubayev
   from Logicworks, Inc. for making SDP replication support possible.

   drbd is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   drbd is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with drbd; see the file COPYING.  If not, write to
   the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.

 */

#include <linux/module.h>
#include <linux/drbd.h>
#include <asm/uaccess.h>
#include <asm/types.h>
#include <net/sock.h>
#include <linux/ctype.h>
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#include <linux/mutex.h>
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#include <linux/fs.h>
#include <linux/file.h>
#include <linux/proc_fs.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/memcontrol.h>
#include <linux/mm_inline.h>
#include <linux/slab.h>
#include <linux/random.h>
#include <linux/reboot.h>
#include <linux/notifier.h>
#include <linux/kthread.h>

#define __KERNEL_SYSCALLS__
#include <linux/unistd.h>
#include <linux/vmalloc.h>

#include <linux/drbd_limits.h>
#include "drbd_int.h"
#include "drbd_req.h" /* only for _req_mod in tl_release and tl_clear */

#include "drbd_vli.h"

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static DEFINE_MUTEX(drbd_main_mutex);
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int drbdd_init(struct drbd_thread *);
int drbd_worker(struct drbd_thread *);
int drbd_asender(struct drbd_thread *);

int drbd_init(void);
static int drbd_open(struct block_device *bdev, fmode_t mode);
static int drbd_release(struct gendisk *gd, fmode_t mode);
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static int w_md_sync(struct drbd_work *w, int unused);
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static void md_sync_timer_fn(unsigned long data);
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static int w_bitmap_io(struct drbd_work *w, int unused);
static int w_go_diskless(struct drbd_work *w, int unused);
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MODULE_AUTHOR("Philipp Reisner <phil@linbit.com>, "
	      "Lars Ellenberg <lars@linbit.com>");
MODULE_DESCRIPTION("drbd - Distributed Replicated Block Device v" REL_VERSION);
MODULE_VERSION(REL_VERSION);
MODULE_LICENSE("GPL");
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MODULE_PARM_DESC(minor_count, "Approximate number of drbd devices ("
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		 __stringify(DRBD_MINOR_COUNT_MIN) "-" __stringify(DRBD_MINOR_COUNT_MAX) ")");
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MODULE_ALIAS_BLOCKDEV_MAJOR(DRBD_MAJOR);

#include <linux/moduleparam.h>
/* allow_open_on_secondary */
MODULE_PARM_DESC(allow_oos, "DONT USE!");
/* thanks to these macros, if compiled into the kernel (not-module),
 * this becomes the boot parameter drbd.minor_count */
module_param(minor_count, uint, 0444);
module_param(disable_sendpage, bool, 0644);
module_param(allow_oos, bool, 0);
module_param(proc_details, int, 0644);

#ifdef CONFIG_DRBD_FAULT_INJECTION
int enable_faults;
int fault_rate;
static int fault_count;
int fault_devs;
/* bitmap of enabled faults */
module_param(enable_faults, int, 0664);
/* fault rate % value - applies to all enabled faults */
module_param(fault_rate, int, 0664);
/* count of faults inserted */
module_param(fault_count, int, 0664);
/* bitmap of devices to insert faults on */
module_param(fault_devs, int, 0644);
#endif

/* module parameter, defined */
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unsigned int minor_count = DRBD_MINOR_COUNT_DEF;
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int disable_sendpage;
int allow_oos;
int proc_details;       /* Detail level in proc drbd*/

/* Module parameter for setting the user mode helper program
 * to run. Default is /sbin/drbdadm */
char usermode_helper[80] = "/sbin/drbdadm";

module_param_string(usermode_helper, usermode_helper, sizeof(usermode_helper), 0644);

/* in 2.6.x, our device mapping and config info contains our virtual gendisks
 * as member "struct gendisk *vdisk;"
 */
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struct idr minors;
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struct list_head drbd_tconns;  /* list of struct drbd_tconn */
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DECLARE_RWSEM(drbd_cfg_rwsem);
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struct kmem_cache *drbd_request_cache;
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struct kmem_cache *drbd_ee_cache;	/* peer requests */
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struct kmem_cache *drbd_bm_ext_cache;	/* bitmap extents */
struct kmem_cache *drbd_al_ext_cache;	/* activity log extents */
mempool_t *drbd_request_mempool;
mempool_t *drbd_ee_mempool;
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mempool_t *drbd_md_io_page_pool;
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struct bio_set *drbd_md_io_bio_set;
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/* I do not use a standard mempool, because:
   1) I want to hand out the pre-allocated objects first.
   2) I want to be able to interrupt sleeping allocation with a signal.
   Note: This is a single linked list, the next pointer is the private
	 member of struct page.
 */
struct page *drbd_pp_pool;
spinlock_t   drbd_pp_lock;
int          drbd_pp_vacant;
wait_queue_head_t drbd_pp_wait;

DEFINE_RATELIMIT_STATE(drbd_ratelimit_state, 5 * HZ, 5);

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static const struct block_device_operations drbd_ops = {
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	.owner =   THIS_MODULE,
	.open =    drbd_open,
	.release = drbd_release,
};

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static void bio_destructor_drbd(struct bio *bio)
{
	bio_free(bio, drbd_md_io_bio_set);
}

struct bio *bio_alloc_drbd(gfp_t gfp_mask)
{
	struct bio *bio;

	if (!drbd_md_io_bio_set)
		return bio_alloc(gfp_mask, 1);

	bio = bio_alloc_bioset(gfp_mask, 1, drbd_md_io_bio_set);
	if (!bio)
		return NULL;
	bio->bi_destructor = bio_destructor_drbd;
	return bio;
}

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#ifdef __CHECKER__
/* When checking with sparse, and this is an inline function, sparse will
   give tons of false positives. When this is a real functions sparse works.
 */
int _get_ldev_if_state(struct drbd_conf *mdev, enum drbd_disk_state mins)
{
	int io_allowed;

	atomic_inc(&mdev->local_cnt);
	io_allowed = (mdev->state.disk >= mins);
	if (!io_allowed) {
		if (atomic_dec_and_test(&mdev->local_cnt))
			wake_up(&mdev->misc_wait);
	}
	return io_allowed;
}

#endif

/**
 * DOC: The transfer log
 *
 * The transfer log is a single linked list of &struct drbd_tl_epoch objects.
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 * mdev->tconn->newest_tle points to the head, mdev->tconn->oldest_tle points to the tail
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 * of the list. There is always at least one &struct drbd_tl_epoch object.
 *
 * Each &struct drbd_tl_epoch has a circular double linked list of requests
 * attached.
 */
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static int tl_init(struct drbd_tconn *tconn)
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{
	struct drbd_tl_epoch *b;

	/* during device minor initialization, we may well use GFP_KERNEL */
	b = kmalloc(sizeof(struct drbd_tl_epoch), GFP_KERNEL);
	if (!b)
		return 0;
	INIT_LIST_HEAD(&b->requests);
	INIT_LIST_HEAD(&b->w.list);
	b->next = NULL;
	b->br_number = 4711;
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	b->n_writes = 0;
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	b->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */

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	tconn->oldest_tle = b;
	tconn->newest_tle = b;
	INIT_LIST_HEAD(&tconn->out_of_sequence_requests);
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	return 1;
}

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static void tl_cleanup(struct drbd_tconn *tconn)
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{
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	if (tconn->oldest_tle != tconn->newest_tle)
		conn_err(tconn, "ASSERT FAILED: oldest_tle == newest_tle\n");
	if (!list_empty(&tconn->out_of_sequence_requests))
		conn_err(tconn, "ASSERT FAILED: list_empty(out_of_sequence_requests)\n");
	kfree(tconn->oldest_tle);
	tconn->oldest_tle = NULL;
	kfree(tconn->unused_spare_tle);
	tconn->unused_spare_tle = NULL;
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}

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/**
 * _tl_add_barrier() - Adds a barrier to the transfer log
 * @mdev:	DRBD device.
 * @new:	Barrier to be added before the current head of the TL.
 *
 * The caller must hold the req_lock.
 */
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void _tl_add_barrier(struct drbd_tconn *tconn, struct drbd_tl_epoch *new)
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{
	struct drbd_tl_epoch *newest_before;

	INIT_LIST_HEAD(&new->requests);
	INIT_LIST_HEAD(&new->w.list);
	new->w.cb = NULL; /* if this is != NULL, we need to dec_ap_pending in tl_clear */
	new->next = NULL;
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	new->n_writes = 0;
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	newest_before = tconn->newest_tle;
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	/* never send a barrier number == 0, because that is special-cased
	 * when using TCQ for our write ordering code */
	new->br_number = (newest_before->br_number+1) ?: 1;
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	if (tconn->newest_tle != new) {
		tconn->newest_tle->next = new;
		tconn->newest_tle = new;
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	}
}

/**
 * tl_release() - Free or recycle the oldest &struct drbd_tl_epoch object of the TL
 * @mdev:	DRBD device.
 * @barrier_nr:	Expected identifier of the DRBD write barrier packet.
 * @set_size:	Expected number of requests before that barrier.
 *
 * In case the passed barrier_nr or set_size does not match the oldest
 * &struct drbd_tl_epoch objects this function will cause a termination
 * of the connection.
 */
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void tl_release(struct drbd_tconn *tconn, unsigned int barrier_nr,
		unsigned int set_size)
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{
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	struct drbd_conf *mdev;
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	struct drbd_tl_epoch *b, *nob; /* next old barrier */
	struct list_head *le, *tle;
	struct drbd_request *r;

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	spin_lock_irq(&tconn->req_lock);
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	b = tconn->oldest_tle;
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	/* first some paranoia code */
	if (b == NULL) {
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		conn_err(tconn, "BAD! BarrierAck #%u received, but no epoch in tl!?\n",
			 barrier_nr);
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		goto bail;
	}
	if (b->br_number != barrier_nr) {
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		conn_err(tconn, "BAD! BarrierAck #%u received, expected #%u!\n",
			 barrier_nr, b->br_number);
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		goto bail;
	}
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	if (b->n_writes != set_size) {
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		conn_err(tconn, "BAD! BarrierAck #%u received with n_writes=%u, expected n_writes=%u!\n",
			 barrier_nr, set_size, b->n_writes);
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		goto bail;
	}

	/* Clean up list of requests processed during current epoch */
	list_for_each_safe(le, tle, &b->requests) {
		r = list_entry(le, struct drbd_request, tl_requests);
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		_req_mod(r, BARRIER_ACKED);
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	}
	/* There could be requests on the list waiting for completion
	   of the write to the local disk. To avoid corruptions of
	   slab's data structures we have to remove the lists head.

	   Also there could have been a barrier ack out of sequence, overtaking
	   the write acks - which would be a bug and violating write ordering.
	   To not deadlock in case we lose connection while such requests are
	   still pending, we need some way to find them for the
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	   _req_mode(CONNECTION_LOST_WHILE_PENDING).
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	   These have been list_move'd to the out_of_sequence_requests list in
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	   _req_mod(, BARRIER_ACKED) above.
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	   */
	list_del_init(&b->requests);
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	mdev = b->w.mdev;
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	nob = b->next;
	if (test_and_clear_bit(CREATE_BARRIER, &mdev->flags)) {
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		_tl_add_barrier(tconn, b);
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		if (nob)
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			tconn->oldest_tle = nob;
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		/* if nob == NULL b was the only barrier, and becomes the new
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		   barrier. Therefore tconn->oldest_tle points already to b */
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	} else {
		D_ASSERT(nob != NULL);
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		tconn->oldest_tle = nob;
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		kfree(b);
	}

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	spin_unlock_irq(&tconn->req_lock);
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	dec_ap_pending(mdev);

	return;

bail:
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	spin_unlock_irq(&tconn->req_lock);
	conn_request_state(tconn, NS(conn, C_PROTOCOL_ERROR), CS_HARD);
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}

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/**
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 * _tl_restart() - Walks the transfer log, and applies an action to all requests
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 * @mdev:	DRBD device.
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 * @what:       The action/event to perform with all request objects
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 *
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 * @what might be one of CONNECTION_LOST_WHILE_PENDING, RESEND, FAIL_FROZEN_DISK_IO,
 * RESTART_FROZEN_DISK_IO.
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 */
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void _tl_restart(struct drbd_tconn *tconn, enum drbd_req_event what)
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{
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	struct drbd_tl_epoch *b, *tmp, **pn;
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	struct list_head *le, *tle, carry_reads;
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	struct drbd_request *req;
	int rv, n_writes, n_reads;
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	b = tconn->oldest_tle;
	pn = &tconn->oldest_tle;
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	while (b) {
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		n_writes = 0;
		n_reads = 0;
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		INIT_LIST_HEAD(&carry_reads);
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		list_for_each_safe(le, tle, &b->requests) {
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			req = list_entry(le, struct drbd_request, tl_requests);
			rv = _req_mod(req, what);

			n_writes += (rv & MR_WRITE) >> MR_WRITE_SHIFT;
			n_reads  += (rv & MR_READ) >> MR_READ_SHIFT;
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		}
		tmp = b->next;

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		if (n_writes) {
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			if (what == RESEND) {
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				b->n_writes = n_writes;
				if (b->w.cb == NULL) {
					b->w.cb = w_send_barrier;
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					inc_ap_pending(b->w.mdev);
					set_bit(CREATE_BARRIER, &b->w.mdev->flags);
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				}

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				drbd_queue_work(&tconn->data.work, &b->w);
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			}
			pn = &b->next;
		} else {
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			if (n_reads)
				list_add(&carry_reads, &b->requests);
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			/* there could still be requests on that ring list,
			 * in case local io is still pending */
			list_del(&b->requests);

			/* dec_ap_pending corresponding to queue_barrier.
			 * the newest barrier may not have been queued yet,
			 * in which case w.cb is still NULL. */
			if (b->w.cb != NULL)
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				dec_ap_pending(b->w.mdev);
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			if (b == tconn->newest_tle) {
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				/* recycle, but reinit! */
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				if (tmp != NULL)
					conn_err(tconn, "ASSERT FAILED tmp == NULL");
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				INIT_LIST_HEAD(&b->requests);
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				list_splice(&carry_reads, &b->requests);
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				INIT_LIST_HEAD(&b->w.list);
				b->w.cb = NULL;
				b->br_number = net_random();
				b->n_writes = 0;

				*pn = b;
				break;
			}
			*pn = tmp;
			kfree(b);
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		}
		b = tmp;
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		list_splice(&carry_reads, &b->requests);
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	}
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}

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/**
 * tl_clear() - Clears all requests and &struct drbd_tl_epoch objects out of the TL
 * @mdev:	DRBD device.
 *
 * This is called after the connection to the peer was lost. The storage covered
 * by the requests on the transfer gets marked as our of sync. Called from the
 * receiver thread and the worker thread.
 */
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void tl_clear(struct drbd_tconn *tconn)
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{
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	struct drbd_conf *mdev;
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	struct list_head *le, *tle;
	struct drbd_request *r;
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	int vnr;
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	spin_lock_irq(&tconn->req_lock);
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	_tl_restart(tconn, CONNECTION_LOST_WHILE_PENDING);
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	/* we expect this list to be empty. */
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	if (!list_empty(&tconn->out_of_sequence_requests))
		conn_err(tconn, "ASSERT FAILED list_empty(&out_of_sequence_requests)\n");
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	/* but just in case, clean it up anyways! */
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	list_for_each_safe(le, tle, &tconn->out_of_sequence_requests) {
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		r = list_entry(le, struct drbd_request, tl_requests);
		/* It would be nice to complete outside of spinlock.
		 * But this is easier for now. */
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		_req_mod(r, CONNECTION_LOST_WHILE_PENDING);
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	}

	/* ensure bit indicating barrier is required is clear */
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	rcu_read_lock();
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	idr_for_each_entry(&tconn->volumes, mdev, vnr)
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		clear_bit(CREATE_BARRIER, &mdev->flags);
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	rcu_read_unlock();
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	spin_unlock_irq(&tconn->req_lock);
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}

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void tl_restart(struct drbd_tconn *tconn, enum drbd_req_event what)
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{
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	spin_lock_irq(&tconn->req_lock);
	_tl_restart(tconn, what);
	spin_unlock_irq(&tconn->req_lock);
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}

static int drbd_thread_setup(void *arg)
{
	struct drbd_thread *thi = (struct drbd_thread *) arg;
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	struct drbd_tconn *tconn = thi->tconn;
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	unsigned long flags;
	int retval;

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	snprintf(current->comm, sizeof(current->comm), "drbd_%c_%s",
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		 thi->name[0], thi->tconn->name);
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restart:
	retval = thi->function(thi);

	spin_lock_irqsave(&thi->t_lock, flags);

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	/* if the receiver has been "EXITING", the last thing it did
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	 * was set the conn state to "StandAlone",
	 * if now a re-connect request comes in, conn state goes C_UNCONNECTED,
	 * and receiver thread will be "started".
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	 * drbd_thread_start needs to set "RESTARTING" in that case.
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	 * t_state check and assignment needs to be within the same spinlock,
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	 * so either thread_start sees EXITING, and can remap to RESTARTING,
	 * or thread_start see NONE, and can proceed as normal.
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	 */

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	if (thi->t_state == RESTARTING) {
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		conn_info(tconn, "Restarting %s thread\n", thi->name);
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		thi->t_state = RUNNING;
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		spin_unlock_irqrestore(&thi->t_lock, flags);
		goto restart;
	}

	thi->task = NULL;
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	thi->t_state = NONE;
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	smp_mb();
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	complete_all(&thi->stop);
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	spin_unlock_irqrestore(&thi->t_lock, flags);

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	conn_info(tconn, "Terminating %s\n", current->comm);
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	/* Release mod reference taken when thread was started */
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	kref_put(&tconn->kref, &conn_destroy);
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	module_put(THIS_MODULE);
	return retval;
}

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static void drbd_thread_init(struct drbd_tconn *tconn, struct drbd_thread *thi,
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			     int (*func) (struct drbd_thread *), char *name)
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{
	spin_lock_init(&thi->t_lock);
	thi->task    = NULL;
523
	thi->t_state = NONE;
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	thi->function = func;
525
	thi->tconn = tconn;
526
	strncpy(thi->name, name, ARRAY_SIZE(thi->name));
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}

int drbd_thread_start(struct drbd_thread *thi)
{
531
	struct drbd_tconn *tconn = thi->tconn;
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	struct task_struct *nt;
	unsigned long flags;

	/* is used from state engine doing drbd_thread_stop_nowait,
	 * while holding the req lock irqsave */
	spin_lock_irqsave(&thi->t_lock, flags);

	switch (thi->t_state) {
540
	case NONE:
541
		conn_info(tconn, "Starting %s thread (from %s [%d])\n",
542
			 thi->name, current->comm, current->pid);
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		/* Get ref on module for thread - this is released when thread exits */
		if (!try_module_get(THIS_MODULE)) {
546
			conn_err(tconn, "Failed to get module reference in drbd_thread_start\n");
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			spin_unlock_irqrestore(&thi->t_lock, flags);
548
			return false;
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		}

551 552
		kref_get(&thi->tconn->kref);

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		init_completion(&thi->stop);
		thi->reset_cpu_mask = 1;
555
		thi->t_state = RUNNING;
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		spin_unlock_irqrestore(&thi->t_lock, flags);
		flush_signals(current); /* otherw. may get -ERESTARTNOINTR */

		nt = kthread_create(drbd_thread_setup, (void *) thi,
560
				    "drbd_%c_%s", thi->name[0], thi->tconn->name);
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		if (IS_ERR(nt)) {
563
			conn_err(tconn, "Couldn't start thread\n");
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565
			kref_put(&tconn->kref, &conn_destroy);
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			module_put(THIS_MODULE);
567
			return false;
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		}
		spin_lock_irqsave(&thi->t_lock, flags);
		thi->task = nt;
571
		thi->t_state = RUNNING;
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		spin_unlock_irqrestore(&thi->t_lock, flags);
		wake_up_process(nt);
		break;
575 576
	case EXITING:
		thi->t_state = RESTARTING;
577
		conn_info(tconn, "Restarting %s thread (from %s [%d])\n",
578
				thi->name, current->comm, current->pid);
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		/* fall through */
580 581
	case RUNNING:
	case RESTARTING:
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	default:
		spin_unlock_irqrestore(&thi->t_lock, flags);
		break;
	}

587
	return true;
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}


void _drbd_thread_stop(struct drbd_thread *thi, int restart, int wait)
{
	unsigned long flags;

595
	enum drbd_thread_state ns = restart ? RESTARTING : EXITING;
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	/* may be called from state engine, holding the req lock irqsave */
	spin_lock_irqsave(&thi->t_lock, flags);

600
	if (thi->t_state == NONE) {
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		spin_unlock_irqrestore(&thi->t_lock, flags);
		if (restart)
			drbd_thread_start(thi);
		return;
	}

	if (thi->t_state != ns) {
		if (thi->task == NULL) {
			spin_unlock_irqrestore(&thi->t_lock, flags);
			return;
		}

		thi->t_state = ns;
		smp_mb();
		init_completion(&thi->stop);
		if (thi->task != current)
			force_sig(DRBD_SIGKILL, thi->task);
	}

	spin_unlock_irqrestore(&thi->t_lock, flags);

	if (wait)
		wait_for_completion(&thi->stop);
}

626
static struct drbd_thread *drbd_task_to_thread(struct drbd_tconn *tconn, struct task_struct *task)
627 628 629 630 631 632 633 634 635
{
	struct drbd_thread *thi =
		task == tconn->receiver.task ? &tconn->receiver :
		task == tconn->asender.task  ? &tconn->asender :
		task == tconn->worker.task   ? &tconn->worker : NULL;

	return thi;
}

636
char *drbd_task_to_thread_name(struct drbd_tconn *tconn, struct task_struct *task)
637
{
638
	struct drbd_thread *thi = drbd_task_to_thread(tconn, task);
639 640 641
	return thi ? thi->name : task->comm;
}

642
int conn_lowest_minor(struct drbd_tconn *tconn)
643
{
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	struct drbd_conf *mdev;
645
	int vnr = 0, m;
646

647
	rcu_read_lock();
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	mdev = idr_get_next(&tconn->volumes, &vnr);
649 650 651 652
	m = mdev ? mdev_to_minor(mdev) : -1;
	rcu_read_unlock();

	return m;
653
}
654 655

#ifdef CONFIG_SMP
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/**
 * drbd_calc_cpu_mask() - Generate CPU masks, spread over all CPUs
 * @mdev:	DRBD device.
 *
 * Forces all threads of a device onto the same CPU. This is beneficial for
 * DRBD's performance. May be overwritten by user's configuration.
 */
663
void drbd_calc_cpu_mask(struct drbd_tconn *tconn)
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{
	int ord, cpu;

	/* user override. */
668
	if (cpumask_weight(tconn->cpu_mask))
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		return;

671
	ord = conn_lowest_minor(tconn) % cpumask_weight(cpu_online_mask);
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	for_each_online_cpu(cpu) {
		if (ord-- == 0) {
674
			cpumask_set_cpu(cpu, tconn->cpu_mask);
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			return;
		}
	}
	/* should not be reached */
679
	cpumask_setall(tconn->cpu_mask);
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}

/**
 * drbd_thread_current_set_cpu() - modifies the cpu mask of the _current_ thread
 * @mdev:	DRBD device.
685
 * @thi:	drbd_thread object
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 *
 * call in the "main loop" of _all_ threads, no need for any mutex, current won't die
 * prematurely.
 */
690
void drbd_thread_current_set_cpu(struct drbd_thread *thi)
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{
	struct task_struct *p = current;
693

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	if (!thi->reset_cpu_mask)
		return;
	thi->reset_cpu_mask = 0;
697
	set_cpus_allowed_ptr(p, thi->tconn->cpu_mask);
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}
#endif

701 702 703 704 705 706 707 708 709
/**
 * drbd_header_size  -  size of a packet header
 *
 * The header size is a multiple of 8, so any payload following the header is
 * word aligned on 64-bit architectures.  (The bitmap send and receive code
 * relies on this.)
 */
unsigned int drbd_header_size(struct drbd_tconn *tconn)
{
710 711 712 713 714 715 716 717 718
	if (tconn->agreed_pro_version >= 100) {
		BUILD_BUG_ON(!IS_ALIGNED(sizeof(struct p_header100), 8));
		return sizeof(struct p_header100);
	} else {
		BUILD_BUG_ON(sizeof(struct p_header80) !=
			     sizeof(struct p_header95));
		BUILD_BUG_ON(!IS_ALIGNED(sizeof(struct p_header80), 8));
		return sizeof(struct p_header80);
	}
719 720
}

721
static unsigned int prepare_header80(struct p_header80 *h, enum drbd_packet cmd, int size)
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{
	h->magic   = cpu_to_be32(DRBD_MAGIC);
	h->command = cpu_to_be16(cmd);
	h->length  = cpu_to_be16(size);
726
	return sizeof(struct p_header80);
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}

729
static unsigned int prepare_header95(struct p_header95 *h, enum drbd_packet cmd, int size)
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{
	h->magic   = cpu_to_be16(DRBD_MAGIC_BIG);
	h->command = cpu_to_be16(cmd);
733
	h->length = cpu_to_be32(size);
734
	return sizeof(struct p_header95);
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}

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static unsigned int prepare_header100(struct p_header100 *h, enum drbd_packet cmd,
				      int size, int vnr)
{
	h->magic = cpu_to_be32(DRBD_MAGIC_100);
	h->volume = cpu_to_be16(vnr);
	h->command = cpu_to_be16(cmd);
	h->length = cpu_to_be32(size);
	h->pad = 0;
	return sizeof(struct p_header100);
}

static unsigned int prepare_header(struct drbd_tconn *tconn, int vnr,
				   void *buffer, enum drbd_packet cmd, int size)
750
{
751 752 753 754
	if (tconn->agreed_pro_version >= 100)
		return prepare_header100(buffer, cmd, size, vnr);
	else if (tconn->agreed_pro_version >= 95 &&
		 size > DRBD_MAX_SIZE_H80_PACKET)
755
		return prepare_header95(buffer, cmd, size);
756
	else
757
		return prepare_header80(buffer, cmd, size);
758 759
}

760 761 762 763 764 765 766 767
static void *__conn_prepare_command(struct drbd_tconn *tconn,
				    struct drbd_socket *sock)
{
	if (!sock->socket)
		return NULL;
	return sock->sbuf + drbd_header_size(tconn);
}

768 769
void *conn_prepare_command(struct drbd_tconn *tconn, struct drbd_socket *sock)
{
770 771
	void *p;

772
	mutex_lock(&sock->mutex);
773 774
	p = __conn_prepare_command(tconn, sock);
	if (!p)
775
		mutex_unlock(&sock->mutex);
776 777

	return p;
778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801
}

void *drbd_prepare_command(struct drbd_conf *mdev, struct drbd_socket *sock)
{
	return conn_prepare_command(mdev->tconn, sock);
}

static int __send_command(struct drbd_tconn *tconn, int vnr,
			  struct drbd_socket *sock, enum drbd_packet cmd,
			  unsigned int header_size, void *data,
			  unsigned int size)
{
	int msg_flags;
	int err;

	/*
	 * Called with @data == NULL and the size of the data blocks in @size
	 * for commands that send data blocks.  For those commands, omit the
	 * MSG_MORE flag: this will increase the likelihood that data blocks
	 * which are page aligned on the sender will end up page aligned on the
	 * receiver.
	 */
	msg_flags = data ? MSG_MORE : 0;

802 803
	header_size += prepare_header(tconn, vnr, sock->sbuf, cmd,
				      header_size + size);
804 805 806 807 808 809 810
	err = drbd_send_all(tconn, sock->socket, sock->sbuf, header_size,
			    msg_flags);
	if (data && !err)
		err = drbd_send_all(tconn, sock->socket, data, size, 0);
	return err;
}

811 812 813 814 815 816 817
static int __conn_send_command(struct drbd_tconn *tconn, struct drbd_socket *sock,
			       enum drbd_packet cmd, unsigned int header_size,
			       void *data, unsigned int size)
{
	return __send_command(tconn, 0, sock, cmd, header_size, data, size);
}

818 819 820 821 822 823
int conn_send_command(struct drbd_tconn *tconn, struct drbd_socket *sock,
		      enum drbd_packet cmd, unsigned int header_size,
		      void *data, unsigned int size)
{
	int err;

824
	err = __conn_send_command(tconn, sock, cmd, header_size, data, size);
825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840
	mutex_unlock(&sock->mutex);
	return err;
}

int drbd_send_command(struct drbd_conf *mdev, struct drbd_socket *sock,
		      enum drbd_packet cmd, unsigned int header_size,
		      void *data, unsigned int size)
{
	int err;

	err = __send_command(mdev->tconn, mdev->vnr, sock, cmd, header_size,
			     data, size);
	mutex_unlock(&sock->mutex);
	return err;
}

841 842
int drbd_send_ping(struct drbd_tconn *tconn)
{
843 844 845 846 847
	struct drbd_socket *sock;

	sock = &tconn->meta;
	if (!conn_prepare_command(tconn, sock))
		return -EIO;
848
	return conn_send_command(tconn, sock, P_PING, 0, NULL, 0);
849 850 851 852
}

int drbd_send_ping_ack(struct drbd_tconn *tconn)
{
853 854 855 856 857
	struct drbd_socket *sock;

	sock = &tconn->meta;
	if (!conn_prepare_command(tconn, sock))
		return -EIO;
858
	return conn_send_command(tconn, sock, P_PING_ACK, 0, NULL, 0);
859 860
}

861
int drbd_send_sync_param(struct drbd_conf *mdev)
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{
863
	struct drbd_socket *sock;
864 865
	struct p_rs_param_95 *p;
	int size;
866
	const int apv = mdev->tconn->agreed_pro_version;
867
	enum drbd_packet cmd;
868
	struct net_conf *nc;
869 870 871 872 873

	sock = &mdev->tconn->data;
	p = drbd_prepare_command(mdev, sock);
	if (!p)
		return -EIO;
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875 876 877
	rcu_read_lock();
	nc = rcu_dereference(mdev->tconn->net_conf);

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	size = apv <= 87 ? sizeof(struct p_rs_param)
		: apv == 88 ? sizeof(struct p_rs_param)
880
			+ strlen(nc->verify_alg) + 1
881 882
		: apv <= 94 ? sizeof(struct p_rs_param_89)
		: /* apv >= 95 */ sizeof(struct p_rs_param_95);
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884
	cmd = apv >= 89 ? P_SYNC_PARAM89 : P_SYNC_PARAM;
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886 887
	/* initialize verify_alg and csums_alg */
	memset(p->verify_alg, 0, 2 * SHARED_SECRET_MAX);
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889 890 891 892 893 894 895 896 897 898 899 900 901 902
	if (get_ldev(mdev)) {
		p->rate = cpu_to_be32(mdev->ldev->dc.resync_rate);
		p->c_plan_ahead = cpu_to_be32(mdev->ldev->dc.c_plan_ahead);
		p->c_delay_target = cpu_to_be32(mdev->ldev->dc.c_delay_target);
		p->c_fill_target = cpu_to_be32(mdev->ldev->dc.c_fill_target);
		p->c_max_rate = cpu_to_be32(mdev->ldev->dc.c_max_rate);
		put_ldev(mdev);
	} else {
		p->rate = cpu_to_be32(DRBD_RATE_DEF);
		p->c_plan_ahead = cpu_to_be32(DRBD_C_PLAN_AHEAD_DEF);
		p->c_delay_target = cpu_to_be32(DRBD_C_DELAY_TARGET_DEF);
		p->c_fill_target = cpu_to_be32(DRBD_C_FILL_TARGET_DEF);
		p->c_max_rate = cpu_to_be32(DRBD_C_MAX_RATE_DEF);
	}
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904
	if (apv >= 88)
905
		strcpy(p->verify_alg, nc->verify_alg);
906
	if (apv >= 89)
907 908
		strcpy(p->csums_alg, nc->csums_alg);
	rcu_read_unlock();
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910
	return drbd_send_command(mdev, sock, cmd, size, NULL, 0);
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}

913
int __drbd_send_protocol(struct drbd_tconn *tconn)
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{
915
	struct drbd_socket *sock;
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	struct p_protocol *p;
917
	struct net_conf *nc;
918
	int size, cf;
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920
	sock = &tconn->data;
921
	p = __conn_prepare_command(tconn, sock);
922 923 924
	if (!p)
		return -EIO;

925 926 927 928 929 930 931 932 933 934
	rcu_read_lock();
	nc = rcu_dereference(tconn->net_conf);

	if (nc->dry_run && tconn->agreed_pro_version < 92) {
		rcu_read_unlock();
		mutex_unlock(&sock->mutex);
		conn_err(tconn, "--dry-run is not supported by peer");
		return -EOPNOTSUPP;
	}

935
	size = sizeof(*p);
936
	if (tconn->agreed_pro_version >= 87)
937
		size += strlen(nc->integrity_alg) + 1;
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939 940 941 942 943
	p->protocol      = cpu_to_be32(nc->wire_protocol);
	p->after_sb_0p   = cpu_to_be32(nc->after_sb_0p);
	p->after_sb_1p   = cpu_to_be32(nc->after_sb_1p);
	p->after_sb_2p   = cpu_to_be32(nc->after_sb_2p);
	p->two_primaries = cpu_to_be32(nc->two_primaries);
944
	cf = 0;
945
	if (nc->want_lose)
946
		cf |= CF_WANT_LOSE;
947
	if (nc->dry_run)
948
		cf |= CF_DRY_RUN;
949 950
	p->conn_flags    = cpu_to_be32(cf);

951
	if (tconn->agreed_pro_version >= 87)
952 953 954
		strcpy(p->integrity_alg, nc->integrity_alg);
	rcu_read_unlock();

955 956 957 958 959 960 961 962 963 964 965 966
	return __conn_send_command(tconn, sock, P_PROTOCOL, size, NULL, 0);
}

int drbd_send_protocol(struct drbd_tconn *tconn)
{
	int err;

	mutex_lock(&tconn->data.mutex);
	err = __drbd_send_protocol(tconn);
	mutex_unlock(&tconn->data.mutex);

	return err;
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}

int _drbd_send_uuids(struct drbd_conf *mdev, u64 uuid_flags)
{
971 972
	struct drbd_socket *sock;
	struct p_uuids *p;
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	int i;

	if (!get_ldev_if_state(mdev, D_NEGOTIATING))
976
		return 0;
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978 979 980 981 982 983
	sock = &mdev->tconn->data;
	p = drbd_prepare_command(mdev, sock);
	if (!p) {
		put_ldev(mdev);
		return -EIO;
	}
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	for (i = UI_CURRENT; i < UI_SIZE; i++)
985
		p->uuid[i] = mdev->ldev ? cpu_to_be64(mdev->ldev->md.uuid[i]) : 0;
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	mdev->comm_bm_set = drbd_bm_total_weight(mdev);
988
	p->uuid[UI_SIZE] = cpu_to_be64(mdev->comm_bm_set);
989 990 991
	rcu_read_lock();
	uuid_flags |= rcu_dereference(mdev->tconn->net_conf)->want_lose ? 1 : 0;
	rcu_read_unlock();
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	uuid_flags |= test_bit(CRASHED_PRIMARY, &mdev->flags) ? 2 : 0;
	uuid_flags |= mdev->new_state_tmp.disk == D_INCONSISTENT ? 4 : 0;
994
	p->uuid[UI_FLAGS] = cpu_to_be64(uuid_flags);
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	put_ldev(mdev);
997
	return drbd_send_command(mdev, sock, P_UUIDS, sizeof(*p), NULL, 0);
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}

int drbd_send_uuids(struct drbd_conf *mdev)
{
	return _drbd_send_uuids(mdev, 0);
}

int drbd_send_uuids_skip_initial_sync(struct drbd_conf *mdev)
{
	return _drbd_send_uuids(mdev, 8);
}

1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027
void drbd_print_uuids(struct drbd_conf *mdev, const char *text)
{
	if (get_ldev_if_state(mdev, D_NEGOTIATING)) {
		u64 *uuid = mdev->ldev->md.uuid;
		dev_info(DEV, "%s %016llX:%016llX:%016llX:%016llX\n",
		     text,
		     (unsigned long long)uuid[UI_CURRENT],
		     (unsigned long long)uuid[UI_BITMAP],
		     (unsigned long long)uuid[UI_HISTORY_START],
		     (unsigned long long)uuid[UI_HISTORY_END]);
		put_ldev(mdev);
	} else {
		dev_info(DEV, "%s effective data uuid: %016llX\n",
				text,
				(unsigned long long)mdev->ed_uuid);
	}
}

1028
void drbd_gen_and_send_sync_uuid(struct drbd_conf *mdev)
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{
1030 1031
	struct drbd_socket *sock;
	struct p_rs_uuid *p;
1032 1033 1034
	u64 uuid;

	D_ASSERT(mdev->state.disk == D_UP_TO_DATE);
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1036
	uuid = mdev->ldev->md.uuid[UI_BITMAP] + UUID_NEW_BM_OFFSET;
1037
	drbd_uuid_set(mdev, UI_BITMAP, uuid);
1038
	drbd_print_uuids(mdev, "updated sync UUID");
1039
	drbd_md_sync(mdev);
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1041 1042 1043 1044 1045 1046
	sock = &mdev->tconn->data;
	p = drbd_prepare_command(mdev, sock);
	if (p) {
		p->uuid = cpu_to_be64(uuid);
		drbd_send_command(mdev, sock, P_SYNC_UUID, sizeof(*p), NULL, 0);
	}
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}

1049
int drbd_send_sizes(struct drbd_conf *mdev, int trigger_reply, enum dds_flags flags)
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{
1051 1052
	struct drbd_socket *sock;
	struct p_sizes *p;
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	sector_t d_size, u_size;
1054
	int q_order_type, max_bio_size;
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	if (get_ldev_if_state(mdev, D_NEGOTIATING)) {
		D_ASSERT(mdev->ldev->backing_bdev);
		d_size = drbd_get_max_capacity(mdev->ldev);
		u_size = mdev->ldev->dc.disk_size;
		q_order_type = drbd_queue_order_type(mdev);
1061 1062
		max_bio_size = queue_max_hw_sectors(mdev->ldev->backing_bdev->bd_disk->queue) << 9;
		max_bio_size = min_t(int, max_bio_size, DRBD_MAX_BIO_SIZE);
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		put_ldev(mdev);
	} else {
		d_size = 0;
		u_size = 0;
		q_order_type = QUEUE_ORDERED_NONE;
1068
		max_bio_size = DRBD_MAX_BIO_SIZE; /* ... multiple BIOs per peer_request */
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	}

1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081
	sock = &mdev->tconn->data;
	p = drbd_prepare_command(mdev, sock);
	if (!p)
		return -EIO;
	p->d_size = cpu_to_be64(d_size);
	p->u_size = cpu_to_be64(u_size);
	p->c_size = cpu_to_be64(trigger_reply ? 0 : drbd_get_capacity(mdev->this_bdev));
	p->max_bio_size = cpu_to_be32(max_bio_size);
	p->queue_order_type = cpu_to_be16(q_order_type);
	p->dds_flags = cpu_to_be16(flags);
	return drbd_send_command(mdev, sock, P_SIZES, sizeof(*p), NULL, 0);
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}

/**
 * drbd_send_state() - Sends the drbd state to the peer
 * @mdev:	DRBD device.
 */
int drbd_send_state(struct drbd_conf *mdev)
{
1090
	struct drbd_socket *sock;
1091
	struct p_state *p;
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1093
	sock = &mdev->tconn->data;
1094 1095 1096 1097 1098 1099
	p = drbd_prepare_command(mdev, sock);
	if (!p)
		return -EIO;
	p->state = cpu_to_be32(mdev->state.i); /* Within the send mutex */
	return drbd_send_command(mdev, sock, P_STATE, sizeof(*p), NULL, 0);
}
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1101 1102 1103 1104
int drbd_send_state_req(struct drbd_conf *mdev, union drbd_state mask, union drbd_state val)
{
	struct drbd_socket *sock;
	struct p_req_state *p;
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1106 1107 1108 1109 1110 1111 1112
	sock = &mdev->tconn->data;
	p = drbd_prepare_command(mdev, sock);
	if (!p)
		return -EIO;
	p->mask = cpu_to_be32(mask.i);
	p->val = cpu_to_be32(val.i);
	return drbd_send_command(mdev, sock, P_STATE_CHG_REQ, sizeof(*p), NULL, 0);
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}

1116
int conn_send_state_req(struct drbd_tconn *tconn, union drbd_state mask, union drbd_state val)
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{
1118 1119 1120
	enum drbd_packet cmd;
	struct drbd_socket *sock;
	struct p_req_state *p;
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1122 1123 1124 1125 1126 1127 1128 1129
	cmd = tconn->agreed_pro_version < 100 ? P_STATE_CHG_REQ : P_CONN_ST_CHG_REQ;
	sock = &tconn->data;
	p = conn_prepare_command(tconn, sock);
	if (!p)
		return -EIO;
	p->mask = cpu_to_be32(mask.i);
	p->val = cpu_to_be32(val.i);
	return conn_send_command(tconn, sock, cmd, sizeof(*p), NULL, 0);
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}

1132
void drbd_send_sr_reply(struct drbd_conf *mdev, enum drbd_state_rv retcode)
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{
1134 1135
	struct drbd_socket *sock;
	struct p_req_state_reply *p;
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1137 1138 1139 1140 1141 1142
	sock = &mdev->tconn->meta;
	p = drbd_prepare_command(mdev, sock);
	if (p) {
		p->retcode = cpu_to_be32(retcode);
		drbd_send_command(mdev, sock, P_STATE_CHG_REPLY, sizeof(*p), NULL, 0);
	}
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}

1145
void conn_send_sr_reply(struct drbd_tconn *tconn, enum drbd_state_rv retcode)
1146
{
1147 1148
	struct drbd_socket *sock;
	struct p_req_state_reply *p;
1149 1150
	enum drbd_packet cmd = tconn->agreed_pro_version < 100 ? P_STATE_CHG_REPLY : P_CONN_ST_CHG_REPLY;

1151 1152 1153 1154 1155 1156
	sock = &tconn->meta;
	p = conn_prepare_command(tconn, sock);
	if (p) {
		p->retcode = cpu_to_be32(retcode);
		conn_send_command(tconn, sock, cmd, sizeof(*p), NULL, 0);
	}
1157 1158
}

1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175
static void dcbp_set_code(struct p_compressed_bm *p, enum drbd_bitmap_code code)
{
	BUG_ON(code & ~0xf);
	p->encoding = (p->encoding & ~0xf) | code;
}

static void dcbp_set_start(struct p_compressed_bm *p, int set)
{
	p->encoding = (p->encoding & ~0x80) | (set ? 0x80 : 0);
}

static void dcbp_set_pad_bits(struct p_compressed_bm *p, int n)
{
	BUG_ON(n & ~0x7);
	p->encoding = (p->encoding & (~0x7 << 4)) | (n << 4);
}

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int fill_bitmap_rle_bits(struct drbd_conf *mdev,
1177 1178 1179
			 struct p_compressed_bm *p,
			 unsigned int size,
			 struct bm_xfer_ctx *c)
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{
	struct bitstream bs;
	unsigned long plain_bits;
	unsigned long tmp;
	unsigned long rl;
	unsigned len;
	unsigned toggle;
1187
	int bits, use_rle;
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	/* may we use this feature? */
1190 1191 1192 1193 1194
	rcu_read_lock();
	use_rle = rcu_dereference(mdev->tconn->net_conf)->use_rle;
	rcu_read_unlock();
	if (!use_rle || mdev->tconn->agreed_pro_version < 90)
		return 0;
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	if (c->bit_offset >= c->bm_bits)
		return 0; /* nothing to do. */

	/* use at most thus many bytes */
1200 1201
	bitstream_init(&bs, p->code, size, 0);
	memset(p->code, 0, size);
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	/* plain bits covered in this code string */
	plain_bits = 0;

	/* p->encoding & 0x80 stores whether the first run length is set.
	 * bit offset is implicit.
	 * start with toggle == 2 to be able to tell the first iteration */
	toggle = 2;

	/* see how much plain bits we can stuff into one packet
	 * using RLE and VLI. */
	do {
		tmp = (toggle == 0) ? _drbd_bm_find_next_zero(mdev, c->bit_offset)
				    : _drbd_bm_find_next(mdev, c->bit_offset);
		if (tmp == -1UL)
			tmp = c->bm_bits;
		rl = tmp - c->bit_offset;

		if (toggle == 2) { /* first iteration */
			if (rl == 0) {
				/* the first checked bit was set,
				 * store start value, */
1223
				dcbp_set_start(p, 1);
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				/* but skip encoding of zero run length */
				toggle = !toggle;
				continue;
			}
1228
			dcbp_set_start(p, 0);
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		}

		/* paranoia: catch zero runlength.
		 * can only happen if bitmap is modified while we scan it. */
		if (rl == 0) {
			dev_err(DEV, "unexpected zero runlength while encoding bitmap "
			    "t:%u bo:%lu\n", toggle, c->bit_offset);
			return -1;
		}

		bits = vli_encode_bits(&bs, rl);
		if (bits == -ENOBUFS) /* buffer full */
			break;
		if (bits <= 0) {
			dev_err(DEV, "error while encoding bitmap: %d\n", bits);
			return 0;
		}

		toggle = !toggle;
		plain_bits += rl;
		c->bit_offset = tmp;
	} while (c->bit_offset < c->bm_bits);

	len = bs.cur.b - p->code + !!bs.cur.bit;

	if (plain_bits < (len << 3)) {
		/* incompressible with this method.
		 * we need to rewind both word and bit position. */
		c->bit_offset -= plain_bits;
		bm_xfer_ctx_bit_to_word_offset(c);
		c->bit_offset = c->word_offset * BITS_PER_LONG;
		return 0;
	}

	/* RLE + VLI was able to compress it just fine.
	 * update c->word_offset. */
	bm_xfer_ctx_bit_to_word_offset(c);

	/* store pad_bits */
1268
	dcbp_set_pad_bits(p, (8 - bs.cur.bit) & 0x7);
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	return len;
}

1273 1274 1275 1276 1277 1278 1279
/**
 * send_bitmap_rle_or_plain
 *
 * Return 0 when done, 1 when another iteration is needed, and a negative error
 * code upon failure.
 */
static int
1280
send_bitmap_rle_or_plain(struct drbd_conf *mdev, struct bm_xfer_ctx *c)
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{
1282
	struct drbd_socket *sock = &mdev->tconn->data;
1283
	unsigned int header_size = drbd_header_size(mdev->tconn);
1284
	struct p_compressed_bm *p = sock->sbuf + header_size;
1285
	int len, err;
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1287 1288
	len = fill_bitmap_rle_bits(mdev, p,
			DRBD_SOCKET_BUFFER_SIZE - header_size - sizeof(*p), c);
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	if (len < 0)
1290
		return -EIO;
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	if (len) {
1293
		dcbp_set_code(p, RLE_VLI_Bits);
1294 1295 1296
		err = __send_command(mdev->tconn, mdev->vnr, sock,
				     P_COMPRESSED_BITMAP, sizeof(*p) + len,
				     NULL, 0);
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		c->packets[0]++;
1298
		c->bytes[0] += header_size + sizeof(*p) + len;
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		if (c->bit_offset >= c->bm_bits)
			len = 0; /* DONE */
	} else {
		/* was not compressible.
		 * send a buffer full of plain text bits instead. */
1305 1306
		unsigned int data_size;
		unsigned long num_words;
1307
		unsigned long *p = sock->sbuf + header_size;
1308 1309

		data_size = DRBD_SOCKET_BUFFER_SIZE - header_size;
1310
		num_words = min_t(size_t, data_size / sizeof(*p),
1311
				  c->bm_words - c->word_offset);
1312
		len = num_words * sizeof(*p);
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		if (len)
1314 1315
			drbd_bm_get_lel(mdev, c->word_offset, num_words, p);
		err = __send_command(mdev->tconn, mdev->vnr, sock, P_BITMAP, len, NULL, 0);
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		c->word_offset += num_words;
		c->bit_offset = c->word_offset * BITS_PER_LONG;

		c->packets[1]++;
1320
		c->bytes[1] += header_size + len;
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		if (c->bit_offset > c->bm_bits)
			c->bit_offset = c->bm_bits;
	}
1325
	if (!err) {
1326 1327 1328 1329 1330 1331 1332
		if (len == 0) {
			INFO_bm_xfer_stats(mdev, "send", c);
			return 0;
		} else
			return 1;
	}
	return -EIO;
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}

/* See the comment at receive_bitmap() */
1336
static int _drbd_send_bitmap(struct drbd_conf *mdev)
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{
	struct bm_xfer_ctx c;
1339
	int err;
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1341 1342
	if (!expect(mdev->bitmap))
		return false;
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	if (get_ldev(mdev)) {
		if (drbd_md_test_flag(mdev->ldev, MDF_FULL_SYNC)) {
			dev_info(DEV, "Writing the whole bitmap, MDF_FullSync was set.\n");
			drbd_bm_set_all(mdev);
			if (drbd_bm_write(mdev)) {
				/* write_bm did fail! Leave full sync flag set in Meta P_DATA
				 * but otherwise process as per normal - need to tell other
				 * side that a full resync is required! */
				dev_err(DEV, "Failed to write bitmap to disk!\n");
			} else {
				drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
				drbd_md_sync(mdev);
			}
		}
		put_ldev(mdev);
	}

	c = (struct bm_xfer_ctx) {
		.bm_bits = drbd_bm_bits(mdev),
		.bm_words = drbd_bm_words(mdev),
	};

	do {
1367
		err = send_bitmap_rle_or_plain(mdev, &c);
1368
	} while (err > 0);
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1370
	return err == 0;
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}

int drbd_send_bitmap(struct drbd_conf *mdev)
{
1375 1376
	struct drbd_socket *sock = &mdev->tconn->data;
	int err = -1;
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1378 1379 1380 1381
	mutex_lock(&sock->mutex);
	if (sock->socket)
		err = !_drbd_send_bitmap(mdev);
	mutex_unlock(&sock->mutex);
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	return err;
}
1384

1385
void drbd_send_b_ack(struct drbd_conf *mdev, u32 barrier_nr, u32 set_size)
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{
1387 1388
	struct drbd_socket *sock;
	struct p_barrier_ack *p;
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1390 1391
	if (mdev->state.conn < C_CONNECTED)
		return;
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1393 1394 1395 1396 1397 1398 1399
	sock = &mdev->tconn->meta;
	p = drbd_prepare_command(mdev, sock);
	if (!p)
		return;
	p->barrier = barrier_nr;
	p->set_size = cpu_to_be32(set_size);
	drbd_send_command(mdev, sock, P_BARRIER_ACK, sizeof(*p), NULL, 0);
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}

/**
 * _drbd_send_ack() - Sends an ack packet
 * @mdev:	DRBD device.
 * @cmd:	Packet command code.
 * @sector:	sector, needs to be in big endian byte order
 * @blksize:	size in byte, needs to be in big endian byte order
 * @block_id:	Id, big endian byte order
 */
1410 1411
static int _drbd_send_ack(struct drbd_conf *mdev, enum drbd_packet cmd,
			  u64 sector, u32 blksize, u64 block_id)
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{
1413 1414
	struct drbd_socket *sock;
	struct p_block_ack *p;
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1416 1417
	if (mdev->state.conn < C_CONNECTED)
		return -EIO;
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1419 1420 1421
	sock = &mdev->tconn->meta;
	p = drbd_prepare_command(mdev, sock);
	if (!p)
1422
		return -EIO;
1423 1424 1425 1426 1427
	p->sector = sector;
	p->block_id = block_id;
	p->blksize = blksize;
	p->seq_num = cpu_to_be32(atomic_inc_return(&mdev->packet_seq));
	return drbd_send_command(mdev, sock, cmd, sizeof(*p), NULL, 0);
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}

1430 1431 1432
/* dp->sector and dp->block_id already/still in network byte order,
 * data_size is payload size according to dp->head,
 * and may need to be corrected for digest size. */
1433 1434
void drbd_send_ack_dp(struct drbd_conf *mdev, enum drbd_packet cmd,
		      struct p_data *dp, int data_size)
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{
1436 1437
	if (mdev->tconn->peer_integrity_tfm)
		data_size -= crypto_hash_digestsize(mdev->tconn->peer_integrity_tfm);
1438 1439
	_drbd_send_ack(mdev, cmd, dp->sector, cpu_to_be32(data_size),
		       dp->block_id);
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}

1442 1443
void drbd_send_ack_rp(struct drbd_conf *mdev, enum drbd_packet cmd,
		      struct p_block_req *rp)
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{
1445
	_drbd_send_ack(mdev, cmd, rp->sector, rp->blksize, rp->block_id);
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}

/**
 * drbd_send_ack() - Sends an ack packet
1450 1451 1452
 * @mdev:	DRBD device
 * @cmd:	packet command code
 * @peer_req:	peer request
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 */
1454
int drbd_send_ack(struct drbd_conf *mdev, enum drbd_packet cmd,
1455
		  struct drbd_peer_request *peer_req)
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{
1457 1458 1459 1460
	return _drbd_send_ack(mdev, cmd,
			      cpu_to_be64(peer_req->i.sector),
			      cpu_to_be32(peer_req->i.size),
			      peer_req->block_id);
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}

/* This function misuses the block_id field to signal if the blocks
 * are is sync or not. */
1465
int drbd_send_ack_ex(struct drbd_conf *mdev, enum drbd_packet cmd,
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		     sector_t sector, int blksize, u64 block_id)
{
1468 1469 1470 1471
	return _drbd_send_ack(mdev, cmd,
			      cpu_to_be64(sector),
			      cpu_to_be32(blksize),
			      cpu_to_be64(block_id));
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}

int drbd_send_drequest(struct drbd_conf *mdev, int cmd,
		       sector_t sector, int size, u64 block_id)
{
1477 1478
	struct drbd_socket *sock;
	struct p_block_req *p;
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1480 1481 1482 1483 1484 1485 1486 1487
	sock = &mdev->tconn->data;
	p = drbd_prepare_command(mdev, sock);
	if (!p)
		return -EIO;
	p->sector = cpu_to_be64(sector);
	p->block_id = block_id;
	p->blksize = cpu_to_be32(size);
	return drbd_send_command(mdev, sock, cmd, sizeof(*p), NULL, 0);
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}

1490 1491
int drbd_send_drequest_csum(struct drbd_conf *mdev, sector_t sector, int size,
			    void *digest, int digest_size, enum drbd_packet cmd)
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{
1493 1494
	struct drbd_socket *sock;
	struct p_block_req *p;
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1496
	/* FIXME: Put the digest into the preallocated socket buffer.  */
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1498 1499 1500 1501 1502 1503 1504 1505 1506
	sock = &mdev->tconn->data;
	p = drbd_prepare_command(mdev, sock);
	if (!p)
		return -EIO;
	p->sector = cpu_to_be64(sector);
	p->block_id = ID_SYNCER /* unused */;
	p->blksize = cpu_to_be32(size);
	return drbd_send_command(mdev, sock, cmd, sizeof(*p),
				 digest, digest_size);
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}

int drbd_send_ov_request(struct drbd_conf *mdev, sector_t sector, int size)
{
1511 1512
	struct drbd_socket *sock;
	struct p_block_req *p;
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1514 1515 1516 1517 1518 1519 1520 1521
	sock = &mdev->tconn->data;
	p = drbd_prepare_command(mdev, sock);
	if (!p)
		return -EIO;
	p->sector = cpu_to_be64(sector);
	p->block_id = ID_SYNCER /* unused */;
	p->blksize = cpu_to_be32(size);
	return drbd_send_command(mdev, sock, P_OV_REQUEST, sizeof(*p), NULL, 0);
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}

/* called on sndtimeo
1525 1526
 * returns false if we should retry,
 * true if we think connection is dead
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 */
1528
static int we_should_drop_the_connection(struct drbd_tconn *tconn, struct socket *sock)
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{
	int drop_it;
	/* long elapsed = (long)(jiffies - mdev->last_received); */

1533 1534 1535
	drop_it =   tconn->meta.socket == sock
		|| !tconn->asender.task
		|| get_t_state(&tconn->asender) != RUNNING
1536
		|| tconn->cstate < C_WF_REPORT_PARAMS;
P
Philipp Reisner 已提交
1537 1538

	if (drop_it)
1539
		return true;
P
Philipp Reisner 已提交
1540

1541
	drop_it = !--tconn->ko_count;
P
Philipp Reisner 已提交
1542
	if (!drop_it) {
1543 1544 1545
		conn_err(tconn, "[%s/%d] sock_sendmsg time expired, ko = %u\n",
			 current->comm, current->pid, tconn->ko_count);
		request_ping(tconn);
P
Philipp Reisner 已提交
1546 1547 1548 1549 1550
	}

	return drop_it; /* && (mdev->state == R_PRIMARY) */;
}

1551
static void drbd_update_congested(struct drbd_tconn *tconn)
1552
{
1553
	struct sock *sk = tconn->data.socket->sk;
1554
	if (sk->sk_wmem_queued > sk->sk_sndbuf * 4 / 5)
1555
		set_bit(NET_CONGESTED, &tconn->flags);
1556 1557
}

P
Philipp Reisner 已提交
1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579
/* The idea of sendpage seems to be to put some kind of reference
 * to the page into the skb, and to hand it over to the NIC. In
 * this process get_page() gets called.
 *
 * As soon as the page was really sent over the network put_page()
 * gets called by some part of the network layer. [ NIC driver? ]
 *
 * [ get_page() / put_page() increment/decrement the count. If count
 *   reaches 0 the page will be freed. ]
 *
 * This works nicely with pages from FSs.
 * But this means that in protocol A we might signal IO completion too early!
 *
 * In order not to corrupt data during a resync we must make sure
 * that we do not reuse our own buffer pages (EEs) to early, therefore
 * we have the net_ee list.
 *
 * XFS seems to have problems, still, it submits pages with page_count == 0!
 * As a workaround, we disable sendpage on pages
 * with page_count == 0 or PageSlab.
 */
static int _drbd_no_send_page(struct drbd_conf *mdev, struct page *page,
1580
			      int offset, size_t size, unsigned msg_flags)
P
Philipp Reisner 已提交
1581
{
1582 1583 1584 1585 1586 1587 1588
	struct socket *socket;
	void *addr;
	int err;

	socket = mdev->tconn->data.socket;
	addr = kmap(page) + offset;
	err = drbd_send_all(mdev->tconn, socket, addr, size, msg_flags);
P
Philipp Reisner 已提交
1589
	kunmap(page);
1590 1591 1592
	if (!err)
		mdev->send_cnt += size >> 9;
	return err;
P
Philipp Reisner 已提交
1593 1594 1595
}

static int _drbd_send_page(struct drbd_conf *mdev, struct page *page,
L
Lars Ellenberg 已提交
1596
		    int offset, size_t size, unsigned msg_flags)
P
Philipp Reisner 已提交
1597
{
1598
	struct socket *socket = mdev->tconn->data.socket;
P
Philipp Reisner 已提交
1599 1600
	mm_segment_t oldfs = get_fs();
	int len = size;
1601
	int err = -EIO;
P
Philipp Reisner 已提交
1602 1603 1604 1605 1606 1607 1608 1609

	/* e.g. XFS meta- & log-data is in slab pages, which have a
	 * page_count of 0 and/or have PageSlab() set.
	 * we cannot use send_page for those, as that does get_page();
	 * put_page(); and would cause either a VM_BUG directly, or
	 * __page_cache_release a page that would actually still be referenced
	 * by someone, leading to some obscure delayed Oops somewhere else. */
	if (disable_sendpage || (page_count(page) < 1) || PageSlab(page))
1610
		return _drbd_no_send_page(mdev, page, offset, size, msg_flags);
P
Philipp Reisner 已提交
1611

L
Lars Ellenberg 已提交
1612
	msg_flags |= MSG_NOSIGNAL;
1613
	drbd_update_congested(mdev->tconn);
P
Philipp Reisner 已提交
1614 1615
	set_fs(KERNEL_DS);
	do {
1616 1617 1618
		int sent;

		sent = socket->ops->sendpage(socket, page, offset, len, msg_flags);
P
Philipp Reisner 已提交
1619
		if (sent <= 0) {
1620 1621 1622 1623 1624
			if (sent == -EAGAIN) {
				if (we_should_drop_the_connection(mdev->tconn, socket))
					break;
				continue;
			}
P
Philipp Reisner 已提交
1625 1626
			dev_warn(DEV, "%s: size=%d len=%d sent=%d\n",
			     __func__, (int)size, len, sent);
1627 1628
			if (sent < 0)
				err = sent;
P
Philipp Reisner 已提交
1629 1630 1631 1632 1633 1634
			break;
		}
		len    -= sent;
		offset += sent;
	} while (len > 0 /* THINK && mdev->cstate >= C_CONNECTED*/);
	set_fs(oldfs);
1635
	clear_bit(NET_CONGESTED, &mdev->tconn->flags);
P
Philipp Reisner 已提交
1636

1637 1638 1639 1640 1641
	if (len == 0) {
		err = 0;
		mdev->send_cnt += size >> 9;
	}
	return err;
P
Philipp Reisner 已提交
1642 1643 1644 1645 1646 1647
}

static int _drbd_send_bio(struct drbd_conf *mdev, struct bio *bio)
{
	struct bio_vec *bvec;
	int i;
L
Lars Ellenberg 已提交
1648
	/* hint all but last page with MSG_MORE */
P
Philipp Reisner 已提交
1649
	__bio_for_each_segment(bvec, bio, i, 0) {
1650 1651 1652 1653 1654 1655 1656
		int err;

		err = _drbd_no_send_page(mdev, bvec->bv_page,
					 bvec->bv_offset, bvec->bv_len,
					 i == bio->bi_vcnt - 1 ? 0 : MSG_MORE);
		if (err)
			return err;
P
Philipp Reisner 已提交
1657
	}
1658
	return 0;
P
Philipp Reisner 已提交
1659 1660 1661 1662 1663 1664
}

static int _drbd_send_zc_bio(struct drbd_conf *mdev, struct bio *bio)
{
	struct bio_vec *bvec;
	int i;
L
Lars Ellenberg 已提交
1665
	/* hint all but last page with MSG_MORE */
P
Philipp Reisner 已提交
1666
	__bio_for_each_segment(bvec, bio, i, 0) {
1667 1668 1669 1670 1671 1672 1673
		int err;

		err = _drbd_send_page(mdev, bvec->bv_page,
				      bvec->bv_offset, bvec->bv_len,
				      i == bio->bi_vcnt - 1 ? 0 : MSG_MORE);
		if (err)
			return err;
P
Philipp Reisner 已提交
1674
	}
1675
	return 0;
P
Philipp Reisner 已提交
1676 1677
}

1678 1679
static int _drbd_send_zc_ee(struct drbd_conf *mdev,
			    struct drbd_peer_request *peer_req)
1680
{
1681 1682
	struct page *page = peer_req->pages;
	unsigned len = peer_req->i.size;
1683
	int err;
1684

L
Lars Ellenberg 已提交
1685
	/* hint all but last page with MSG_MORE */
1686 1687
	page_chain_for_each(page) {
		unsigned l = min_t(unsigned, len, PAGE_SIZE);
1688 1689 1690 1691 1692

		err = _drbd_send_page(mdev, page, 0, l,
				      page_chain_next(page) ? MSG_MORE : 0);
		if (err)
			return err;
1693 1694
		len -= l;
	}
1695
	return 0;
1696 1697
}

1698 1699
static u32 bio_flags_to_wire(struct drbd_conf *mdev, unsigned long bi_rw)
{
1700
	if (mdev->tconn->agreed_pro_version >= 95)
1701 1702 1703 1704 1705
		return  (bi_rw & REQ_SYNC ? DP_RW_SYNC : 0) |
			(bi_rw & REQ_FUA ? DP_FUA : 0) |
			(bi_rw & REQ_FLUSH ? DP_FLUSH : 0) |
			(bi_rw & REQ_DISCARD ? DP_DISCARD : 0);
	else
J
Jens Axboe 已提交
1706
		return bi_rw & REQ_SYNC ? DP_RW_SYNC : 0;
1707 1708
}

P
Philipp Reisner 已提交
1709 1710 1711 1712 1713
/* Used to send write requests
 * R_PRIMARY -> Peer	(P_DATA)
 */
int drbd_send_dblock(struct drbd_conf *mdev, struct drbd_request *req)
{
1714 1715
	struct drbd_socket *sock;
	struct p_data *p;
P
Philipp Reisner 已提交
1716 1717
	unsigned int dp_flags = 0;
	int dgs;
1718
	int err;
P
Philipp Reisner 已提交
1719

1720 1721
	dgs = (mdev->tconn->agreed_pro_version >= 87 && mdev->tconn->integrity_tfm) ?
		crypto_hash_digestsize(mdev->tconn->integrity_tfm) : 0;
P
Philipp Reisner 已提交
1722

1723 1724 1725 1726 1727 1728 1729
	sock = &mdev->tconn->data;
	p = drbd_prepare_command(mdev, sock);
	if (!p)
		return -EIO;
	p->sector = cpu_to_be64(req->i.sector);
	p->block_id = (unsigned long)req;
	p->seq_num = cpu_to_be32(req->seq_num = atomic_inc_return(&mdev->packet_seq));
1730
	dp_flags = bio_flags_to_wire(mdev, req->master_bio->bi_rw);
P
Philipp Reisner 已提交
1731 1732 1733
	if (mdev->state.conn >= C_SYNC_SOURCE &&
	    mdev->state.conn <= C_PAUSED_SYNC_T)
		dp_flags |= DP_MAY_SET_IN_SYNC;
1734 1735 1736 1737 1738 1739
	if (mdev->tconn->agreed_pro_version >= 100) {
		if (req->rq_state & RQ_EXP_RECEIVE_ACK)
			dp_flags |= DP_SEND_RECEIVE_ACK;
		if (req->rq_state & RQ_EXP_WRITE_ACK)
			dp_flags |= DP_SEND_WRITE_ACK;
	}
1740 1741
	p->dp_flags = cpu_to_be32(dp_flags);
	if (dgs)
1742
		drbd_csum_bio(mdev, mdev->tconn->integrity_tfm, req->master_bio, p + 1);
1743
	err = __send_command(mdev->tconn, mdev->vnr, sock, P_DATA, sizeof(*p) + dgs, NULL, req->i.size);
1744
	if (!err) {
1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755
		/* For protocol A, we have to memcpy the payload into
		 * socket buffers, as we may complete right away
		 * as soon as we handed it over to tcp, at which point the data
		 * pages may become invalid.
		 *
		 * For data-integrity enabled, we copy it as well, so we can be
		 * sure that even if the bio pages may still be modified, it
		 * won't change the data on the wire, thus if the digest checks
		 * out ok after sending on this side, but does not fit on the
		 * receiving side, we sure have detected corruption elsewhere.
		 */
1756
		if (!(req->rq_state & (RQ_EXP_RECEIVE_ACK | RQ_EXP_WRITE_ACK)) || dgs)
1757
			err = _drbd_send_bio(mdev, req->master_bio);
P
Philipp Reisner 已提交
1758
		else
1759
			err = _drbd_send_zc_bio(mdev, req->master_bio);
1760 1761 1762

		/* double check digest, sometimes buffers have been modified in flight. */
		if (dgs > 0 && dgs <= 64) {
B
Bart Van Assche 已提交
1763
			/* 64 byte, 512 bit, is the largest digest size
1764 1765
			 * currently supported in kernel crypto. */
			unsigned char digest[64];
1766
			drbd_csum_bio(mdev, mdev->tconn->integrity_tfm, req->master_bio, digest);
1767
			if (memcmp(p + 1, digest, dgs)) {
1768 1769
				dev_warn(DEV,
					"Digest mismatch, buffer modified by upper layers during write: %llus +%u\n",
1770
					(unsigned long long)req->i.sector, req->i.size);
1771 1772 1773 1774
			}
		} /* else if (dgs > 64) {
		     ... Be noisy about digest too large ...
		} */
P
Philipp Reisner 已提交
1775
	}
1776
	mutex_unlock(&sock->mutex);  /* locked by drbd_prepare_command() */
1777

1778
	return err;
P
Philipp Reisner 已提交
1779 1780 1781 1782 1783 1784
}

/* answer packet, used to send data back for read requests:
 *  Peer       -> (diskless) R_PRIMARY   (P_DATA_REPLY)
 *  C_SYNC_SOURCE -> C_SYNC_TARGET         (P_RS_DATA_REPLY)
 */
1785
int drbd_send_block(struct drbd_conf *mdev, enum drbd_packet cmd,
1786
		    struct drbd_peer_request *peer_req)
P
Philipp Reisner 已提交
1787
{
1788 1789
	struct drbd_socket *sock;
	struct p_data *p;
1790
	int err;
P
Philipp Reisner 已提交
1791 1792
	int dgs;

1793 1794
	dgs = (mdev->tconn->agreed_pro_version >= 87 && mdev->tconn->integrity_tfm) ?
		crypto_hash_digestsize(mdev->tconn->integrity_tfm) : 0;
P
Philipp Reisner 已提交
1795

1796 1797 1798 1799 1800 1801 1802 1803
	sock = &mdev->tconn->data;
	p = drbd_prepare_command(mdev, sock);
	if (!p)
		return -EIO;
	p->sector = cpu_to_be64(peer_req->i.sector);
	p->block_id = peer_req->block_id;
	p->seq_num = 0;  /* unused */
	if (dgs)
1804
		drbd_csum_ee(mdev, mdev->tconn->integrity_tfm, peer_req, p + 1);
1805
	err = __send_command(mdev->tconn, mdev->vnr, sock, cmd, sizeof(*p) + dgs, NULL, peer_req->i.size);
1806 1807
	if (!err)
		err = _drbd_send_zc_ee(mdev, peer_req);
1808
	mutex_unlock(&sock->mutex);  /* locked by drbd_prepare_command() */
1809

1810
	return err;
P
Philipp Reisner 已提交
1811 1812
}

1813
int drbd_send_out_of_sync(struct drbd_conf *mdev, struct drbd_request *req)
1814
{
1815 1816
	struct drbd_socket *sock;
	struct p_block_desc *p;
1817

1818 1819 1820 1821 1822 1823 1824
	sock = &mdev->tconn->data;
	p = drbd_prepare_command(mdev, sock);
	if (!p)
		return -EIO;
	p->sector = cpu_to_be64(req->i.sector);
	p->blksize = cpu_to_be32(req->i.size);
	return drbd_send_command(mdev, sock, P_OUT_OF_SYNC, sizeof(*p), NULL, 0);
1825 1826
}

P
Philipp Reisner 已提交
1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842
/*
  drbd_send distinguishes two cases:

  Packets sent via the data socket "sock"
  and packets sent via the meta data socket "msock"

		    sock                      msock
  -----------------+-------------------------+------------------------------
  timeout           conf.timeout / 2          conf.timeout / 2
  timeout action    send a ping via msock     Abort communication
					      and close all sockets
*/

/*
 * you must have down()ed the appropriate [m]sock_mutex elsewhere!
 */
1843
int drbd_send(struct drbd_tconn *tconn, struct socket *sock,
P
Philipp Reisner 已提交
1844 1845 1846 1847 1848 1849 1850
	      void *buf, size_t size, unsigned msg_flags)
{
	struct kvec iov;
	struct msghdr msg;
	int rv, sent = 0;

	if (!sock)
1851
		return -EBADR;
P
Philipp Reisner 已提交
1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863

	/* THINK  if (signal_pending) return ... ? */

	iov.iov_base = buf;
	iov.iov_len  = size;

	msg.msg_name       = NULL;
	msg.msg_namelen    = 0;
	msg.msg_control    = NULL;
	msg.msg_controllen = 0;
	msg.msg_flags      = msg_flags | MSG_NOSIGNAL;

1864
	if (sock == tconn->data.socket) {
1865 1866 1867
		rcu_read_lock();
		tconn->ko_count = rcu_dereference(tconn->net_conf)->ko_count;
		rcu_read_unlock();
1868
		drbd_update_congested(tconn);
P
Philipp Reisner 已提交
1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881
	}
	do {
		/* STRANGE
		 * tcp_sendmsg does _not_ use its size parameter at all ?
		 *
		 * -EAGAIN on timeout, -EINTR on signal.
		 */
/* THINK
 * do we need to block DRBD_SIG if sock == &meta.socket ??
 * otherwise wake_asender() might interrupt some send_*Ack !
 */
		rv = kernel_sendmsg(sock, &msg, &iov, 1, size);
		if (rv == -EAGAIN) {
1882
			if (we_should_drop_the_connection(tconn, sock))
P
Philipp Reisner 已提交
1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897
				break;
			else
				continue;
		}
		if (rv == -EINTR) {
			flush_signals(current);
			rv = 0;
		}
		if (rv < 0)
			break;
		sent += rv;
		iov.iov_base += rv;
		iov.iov_len  -= rv;
	} while (sent < size);

1898 1899
	if (sock == tconn->data.socket)
		clear_bit(NET_CONGESTED, &tconn->flags);
P
Philipp Reisner 已提交
1900 1901 1902

	if (rv <= 0) {
		if (rv != -EAGAIN) {
1903 1904 1905
			conn_err(tconn, "%s_sendmsg returned %d\n",
				 sock == tconn->meta.socket ? "msock" : "sock",
				 rv);
1906
			conn_request_state(tconn, NS(conn, C_BROKEN_PIPE), CS_HARD);
P
Philipp Reisner 已提交
1907
		} else
1908
			conn_request_state(tconn, NS(conn, C_TIMEOUT), CS_HARD);
P
Philipp Reisner 已提交
1909 1910 1911 1912 1913
	}

	return sent;
}

1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931
/**
 * drbd_send_all  -  Send an entire buffer
 *
 * Returns 0 upon success and a negative error value otherwise.
 */
int drbd_send_all(struct drbd_tconn *tconn, struct socket *sock, void *buffer,
		  size_t size, unsigned msg_flags)
{
	int err;

	err = drbd_send(tconn, sock, buffer, size, msg_flags);
	if (err < 0)
		return err;
	if (err != size)
		return -EIO;
	return 0;
}

P
Philipp Reisner 已提交
1932 1933 1934 1935 1936 1937
static int drbd_open(struct block_device *bdev, fmode_t mode)
{
	struct drbd_conf *mdev = bdev->bd_disk->private_data;
	unsigned long flags;
	int rv = 0;

1938
	mutex_lock(&drbd_main_mutex);
1939
	spin_lock_irqsave(&mdev->tconn->req_lock, flags);
P
Philipp Reisner 已提交
1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951
	/* to have a stable mdev->state.role
	 * and no race with updating open_cnt */

	if (mdev->state.role != R_PRIMARY) {
		if (mode & FMODE_WRITE)
			rv = -EROFS;
		else if (!allow_oos)
			rv = -EMEDIUMTYPE;
	}

	if (!rv)
		mdev->open_cnt++;
1952
	spin_unlock_irqrestore(&mdev->tconn->req_lock, flags);
1953
	mutex_unlock(&drbd_main_mutex);
P
Philipp Reisner 已提交
1954 1955 1956 1957 1958 1959 1960

	return rv;
}

static int drbd_release(struct gendisk *gd, fmode_t mode)
{
	struct drbd_conf *mdev = gd->private_data;
1961
	mutex_lock(&drbd_main_mutex);
P
Philipp Reisner 已提交
1962
	mdev->open_cnt--;
1963
	mutex_unlock(&drbd_main_mutex);
P
Philipp Reisner 已提交
1964 1965 1966 1967 1968
	return 0;
}

static void drbd_set_defaults(struct drbd_conf *mdev)
{
1969 1970
	/* Beware! The actual layout differs
	 * between big endian and little endian */
1971
	mdev->state = (union drbd_dev_state) {
P
Philipp Reisner 已提交
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991
		{ .role = R_SECONDARY,
		  .peer = R_UNKNOWN,
		  .conn = C_STANDALONE,
		  .disk = D_DISKLESS,
		  .pdsk = D_UNKNOWN,
		} };
}

void drbd_init_set_defaults(struct drbd_conf *mdev)
{
	/* the memset(,0,) did most of this.
	 * note: only assignments, no allocation in here */

	drbd_set_defaults(mdev);

	atomic_set(&mdev->ap_bio_cnt, 0);
	atomic_set(&mdev->ap_pending_cnt, 0);
	atomic_set(&mdev->rs_pending_cnt, 0);
	atomic_set(&mdev->unacked_cnt, 0);
	atomic_set(&mdev->local_cnt, 0);
1992
	atomic_set(&mdev->pp_in_use_by_net, 0);
1993
	atomic_set(&mdev->rs_sect_in, 0);
1994
	atomic_set(&mdev->rs_sect_ev, 0);
1995
	atomic_set(&mdev->ap_in_flight, 0);
P
Philipp Reisner 已提交
1996 1997

	mutex_init(&mdev->md_io_mutex);
1998 1999
	mutex_init(&mdev->own_state_mutex);
	mdev->state_mutex = &mdev->own_state_mutex;
P
Philipp Reisner 已提交
2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

	spin_lock_init(&mdev->al_lock);
	spin_lock_init(&mdev->peer_seq_lock);
	spin_lock_init(&mdev->epoch_lock);

	INIT_LIST_HEAD(&mdev->active_ee);
	INIT_LIST_HEAD(&mdev->sync_ee);
	INIT_LIST_HEAD(&mdev->done_ee);
	INIT_LIST_HEAD(&mdev->read_ee);
	INIT_LIST_HEAD(&mdev->net_ee);
	INIT_LIST_HEAD(&mdev->resync_reads);
	INIT_LIST_HEAD(&mdev->resync_work.list);
	INIT_LIST_HEAD(&mdev->unplug_work.list);
2013
	INIT_LIST_HEAD(&mdev->go_diskless.list);
P
Philipp Reisner 已提交
2014
	INIT_LIST_HEAD(&mdev->md_sync_work.list);
2015
	INIT_LIST_HEAD(&mdev->start_resync_work.list);
P
Philipp Reisner 已提交
2016
	INIT_LIST_HEAD(&mdev->bm_io_work.w.list);
2017

2018
	mdev->resync_work.cb  = w_resync_timer;
P
Philipp Reisner 已提交
2019
	mdev->unplug_work.cb  = w_send_write_hint;
2020
	mdev->go_diskless.cb  = w_go_diskless;
P
Philipp Reisner 已提交
2021 2022
	mdev->md_sync_work.cb = w_md_sync;
	mdev->bm_io_work.w.cb = w_bitmap_io;
2023
	mdev->start_resync_work.cb = w_start_resync;
2024 2025 2026 2027 2028 2029 2030 2031

	mdev->resync_work.mdev  = mdev;
	mdev->unplug_work.mdev  = mdev;
	mdev->go_diskless.mdev  = mdev;
	mdev->md_sync_work.mdev = mdev;
	mdev->bm_io_work.w.mdev = mdev;
	mdev->start_resync_work.mdev = mdev;

P
Philipp Reisner 已提交
2032 2033
	init_timer(&mdev->resync_timer);
	init_timer(&mdev->md_sync_timer);
2034
	init_timer(&mdev->start_resync_timer);
2035
	init_timer(&mdev->request_timer);
P
Philipp Reisner 已提交
2036 2037 2038 2039
	mdev->resync_timer.function = resync_timer_fn;
	mdev->resync_timer.data = (unsigned long) mdev;
	mdev->md_sync_timer.function = md_sync_timer_fn;
	mdev->md_sync_timer.data = (unsigned long) mdev;
2040 2041
	mdev->start_resync_timer.function = start_resync_timer_fn;
	mdev->start_resync_timer.data = (unsigned long) mdev;
2042 2043
	mdev->request_timer.function = request_timer_fn;
	mdev->request_timer.data = (unsigned long) mdev;
P
Philipp Reisner 已提交
2044 2045 2046 2047 2048 2049 2050

	init_waitqueue_head(&mdev->misc_wait);
	init_waitqueue_head(&mdev->state_wait);
	init_waitqueue_head(&mdev->ee_wait);
	init_waitqueue_head(&mdev->al_wait);
	init_waitqueue_head(&mdev->seq_wait);

P
Philipp Reisner 已提交
2051
	/* mdev->tconn->agreed_pro_version gets initialized in drbd_connect() */
2052
	mdev->write_ordering = WO_bdev_flush;
P
Philipp Reisner 已提交
2053
	mdev->resync_wenr = LC_FREE;
2054 2055
	mdev->peer_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE;
	mdev->local_max_bio_size = DRBD_MAX_BIO_SIZE_SAFE;
P
Philipp Reisner 已提交
2056 2057 2058 2059
}

void drbd_mdev_cleanup(struct drbd_conf *mdev)
{
2060
	int i;
2061
	if (mdev->tconn->receiver.t_state != NONE)
P
Philipp Reisner 已提交
2062
		dev_err(DEV, "ASSERT FAILED: receiver t_state == %d expected 0.\n",
2063
				mdev->tconn->receiver.t_state);
P
Philipp Reisner 已提交
2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076

	/* no need to lock it, I'm the only thread alive */
	if (atomic_read(&mdev->current_epoch->epoch_size) !=  0)
		dev_err(DEV, "epoch_size:%d\n", atomic_read(&mdev->current_epoch->epoch_size));
	mdev->al_writ_cnt  =
	mdev->bm_writ_cnt  =
	mdev->read_cnt     =
	mdev->recv_cnt     =
	mdev->send_cnt     =
	mdev->writ_cnt     =
	mdev->p_size       =
	mdev->rs_start     =
	mdev->rs_total     =
2077 2078
	mdev->rs_failed    = 0;
	mdev->rs_last_events = 0;
2079
	mdev->rs_last_sect_ev = 0;
2080 2081 2082 2083
	for (i = 0; i < DRBD_SYNC_MARKS; i++) {
		mdev->rs_mark_left[i] = 0;
		mdev->rs_mark_time[i] = 0;
	}
2084
	D_ASSERT(mdev->tconn->net_conf == NULL);
P
Philipp Reisner 已提交
2085 2086 2087 2088

	drbd_set_my_capacity(mdev, 0);
	if (mdev->bitmap) {
		/* maybe never allocated. */
2089
		drbd_bm_resize(mdev, 0, 1);
P
Philipp Reisner 已提交
2090 2091 2092
		drbd_bm_cleanup(mdev);
	}

2093 2094 2095
	drbd_free_bc(mdev->ldev);
	mdev->ldev = NULL;

2096
	clear_bit(AL_SUSPENDED, &mdev->flags);
P
Philipp Reisner 已提交
2097 2098 2099 2100 2101 2102 2103

	D_ASSERT(list_empty(&mdev->active_ee));
	D_ASSERT(list_empty(&mdev->sync_ee));
	D_ASSERT(list_empty(&mdev->done_ee));
	D_ASSERT(list_empty(&mdev->read_ee));
	D_ASSERT(list_empty(&mdev->net_ee));
	D_ASSERT(list_empty(&mdev->resync_reads));
2104 2105
	D_ASSERT(list_empty(&mdev->tconn->data.work.q));
	D_ASSERT(list_empty(&mdev->tconn->meta.work.q));
P
Philipp Reisner 已提交
2106 2107
	D_ASSERT(list_empty(&mdev->resync_work.list));
	D_ASSERT(list_empty(&mdev->unplug_work.list));
2108
	D_ASSERT(list_empty(&mdev->go_diskless.list));
2109 2110

	drbd_set_defaults(mdev);
P
Philipp Reisner 已提交
2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126
}


static void drbd_destroy_mempools(void)
{
	struct page *page;

	while (drbd_pp_pool) {
		page = drbd_pp_pool;
		drbd_pp_pool = (struct page *)page_private(page);
		__free_page(page);
		drbd_pp_vacant--;
	}

	/* D_ASSERT(atomic_read(&drbd_pp_vacant)==0); */

2127 2128
	if (drbd_md_io_bio_set)
		bioset_free(drbd_md_io_bio_set);
2129 2130
	if (drbd_md_io_page_pool)
		mempool_destroy(drbd_md_io_page_pool);
P
Philipp Reisner 已提交
2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143
	if (drbd_ee_mempool)
		mempool_destroy(drbd_ee_mempool);
	if (drbd_request_mempool)
		mempool_destroy(drbd_request_mempool);
	if (drbd_ee_cache)
		kmem_cache_destroy(drbd_ee_cache);
	if (drbd_request_cache)
		kmem_cache_destroy(drbd_request_cache);
	if (drbd_bm_ext_cache)
		kmem_cache_destroy(drbd_bm_ext_cache);
	if (drbd_al_ext_cache)
		kmem_cache_destroy(drbd_al_ext_cache);

2144
	drbd_md_io_bio_set   = NULL;
2145
	drbd_md_io_page_pool = NULL;
P
Philipp Reisner 已提交
2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158
	drbd_ee_mempool      = NULL;
	drbd_request_mempool = NULL;
	drbd_ee_cache        = NULL;
	drbd_request_cache   = NULL;
	drbd_bm_ext_cache    = NULL;
	drbd_al_ext_cache    = NULL;

	return;
}

static int drbd_create_mempools(void)
{
	struct page *page;
2159
	const int number = (DRBD_MAX_BIO_SIZE/PAGE_SIZE) * minor_count;
P
Philipp Reisner 已提交
2160 2161 2162 2163 2164 2165 2166 2167 2168
	int i;

	/* prepare our caches and mempools */
	drbd_request_mempool = NULL;
	drbd_ee_cache        = NULL;
	drbd_request_cache   = NULL;
	drbd_bm_ext_cache    = NULL;
	drbd_al_ext_cache    = NULL;
	drbd_pp_pool         = NULL;
2169
	drbd_md_io_page_pool = NULL;
2170
	drbd_md_io_bio_set   = NULL;
P
Philipp Reisner 已提交
2171 2172 2173 2174 2175 2176 2177 2178

	/* caches */
	drbd_request_cache = kmem_cache_create(
		"drbd_req", sizeof(struct drbd_request), 0, 0, NULL);
	if (drbd_request_cache == NULL)
		goto Enomem;

	drbd_ee_cache = kmem_cache_create(
2179
		"drbd_ee", sizeof(struct drbd_peer_request), 0, 0, NULL);
P
Philipp Reisner 已提交
2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193
	if (drbd_ee_cache == NULL)
		goto Enomem;

	drbd_bm_ext_cache = kmem_cache_create(
		"drbd_bm", sizeof(struct bm_extent), 0, 0, NULL);
	if (drbd_bm_ext_cache == NULL)
		goto Enomem;

	drbd_al_ext_cache = kmem_cache_create(
		"drbd_al", sizeof(struct lc_element), 0, 0, NULL);
	if (drbd_al_ext_cache == NULL)
		goto Enomem;

	/* mempools */
2194 2195 2196 2197
	drbd_md_io_bio_set = bioset_create(DRBD_MIN_POOL_PAGES, 0);
	if (drbd_md_io_bio_set == NULL)
		goto Enomem;

2198 2199 2200 2201
	drbd_md_io_page_pool = mempool_create_page_pool(DRBD_MIN_POOL_PAGES, 0);
	if (drbd_md_io_page_pool == NULL)
		goto Enomem;

P
Philipp Reisner 已提交
2202 2203 2204 2205 2206 2207 2208
	drbd_request_mempool = mempool_create(number,
		mempool_alloc_slab, mempool_free_slab, drbd_request_cache);
	if (drbd_request_mempool == NULL)
		goto Enomem;

	drbd_ee_mempool = mempool_create(number,
		mempool_alloc_slab, mempool_free_slab, drbd_ee_cache);
2209
	if (drbd_ee_mempool == NULL)
P
Philipp Reisner 已提交
2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244
		goto Enomem;

	/* drbd's page pool */
	spin_lock_init(&drbd_pp_lock);

	for (i = 0; i < number; i++) {
		page = alloc_page(GFP_HIGHUSER);
		if (!page)
			goto Enomem;
		set_page_private(page, (unsigned long)drbd_pp_pool);
		drbd_pp_pool = page;
	}
	drbd_pp_vacant = number;

	return 0;

Enomem:
	drbd_destroy_mempools(); /* in case we allocated some */
	return -ENOMEM;
}

static int drbd_notify_sys(struct notifier_block *this, unsigned long code,
	void *unused)
{
	/* just so we have it.  you never know what interesting things we
	 * might want to do here some day...
	 */

	return NOTIFY_DONE;
}

static struct notifier_block drbd_notifier = {
	.notifier_call = drbd_notify_sys,
};

2245
static void drbd_release_all_peer_reqs(struct drbd_conf *mdev)
P
Philipp Reisner 已提交
2246 2247 2248
{
	int rr;

2249
	rr = drbd_free_peer_reqs(mdev, &mdev->active_ee);
P
Philipp Reisner 已提交
2250 2251 2252
	if (rr)
		dev_err(DEV, "%d EEs in active list found!\n", rr);

2253
	rr = drbd_free_peer_reqs(mdev, &mdev->sync_ee);
P
Philipp Reisner 已提交
2254 2255 2256
	if (rr)
		dev_err(DEV, "%d EEs in sync list found!\n", rr);

2257
	rr = drbd_free_peer_reqs(mdev, &mdev->read_ee);
P
Philipp Reisner 已提交
2258 2259 2260
	if (rr)
		dev_err(DEV, "%d EEs in read list found!\n", rr);

2261
	rr = drbd_free_peer_reqs(mdev, &mdev->done_ee);
P
Philipp Reisner 已提交
2262 2263 2264
	if (rr)
		dev_err(DEV, "%d EEs in done list found!\n", rr);

2265
	rr = drbd_free_peer_reqs(mdev, &mdev->net_ee);
P
Philipp Reisner 已提交
2266 2267 2268 2269
	if (rr)
		dev_err(DEV, "%d EEs in net list found!\n", rr);
}

2270
/* caution. no locking. */
2271
void drbd_delete_device(struct drbd_conf *mdev)
P
Philipp Reisner 已提交
2272
{
2273 2274
	struct drbd_tconn *tconn = mdev->tconn;

2275
	idr_remove(&mdev->tconn->volumes, mdev->vnr);
2276
	idr_remove(&minors, mdev_to_minor(mdev));
2277
	synchronize_rcu();
2278

P
Philipp Reisner 已提交
2279
	/* paranoia asserts */
2280
	D_ASSERT(mdev->open_cnt == 0);
2281
	D_ASSERT(list_empty(&mdev->tconn->data.work.q));
P
Philipp Reisner 已提交
2282 2283 2284 2285 2286 2287 2288 2289 2290 2291
	/* end paranoia asserts */

	del_gendisk(mdev->vdisk);

	/* cleanup stuff that may have been allocated during
	 * device (re-)configuration or state changes */

	if (mdev->this_bdev)
		bdput(mdev->this_bdev);

2292 2293
	drbd_free_bc(mdev->ldev);
	mdev->ldev = NULL;
P
Philipp Reisner 已提交
2294

2295
	drbd_release_all_peer_reqs(mdev);
P
Philipp Reisner 已提交
2296 2297 2298 2299 2300 2301 2302

	lc_destroy(mdev->act_log);
	lc_destroy(mdev->resync);

	kfree(mdev->p_uuid);
	/* mdev->p_uuid = NULL; */

2303 2304 2305 2306 2307 2308 2309
	kfree(mdev->current_epoch);
	if (mdev->bitmap) /* should no longer be there. */
		drbd_bm_cleanup(mdev);
	__free_page(mdev->md_io_page);
	put_disk(mdev->vdisk);
	blk_cleanup_queue(mdev->rq_queue);
	kfree(mdev);
2310 2311

	kref_put(&tconn->kref, &conn_destroy);
P
Philipp Reisner 已提交
2312 2313 2314 2315 2316
}

static void drbd_cleanup(void)
{
	unsigned int i;
2317
	struct drbd_conf *mdev;
P
Philipp Reisner 已提交
2318 2319 2320

	unregister_reboot_notifier(&drbd_notifier);

2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331
	/* first remove proc,
	 * drbdsetup uses it's presence to detect
	 * whether DRBD is loaded.
	 * If we would get stuck in proc removal,
	 * but have netlink already deregistered,
	 * some drbdsetup commands may wait forever
	 * for an answer.
	 */
	if (drbd_proc)
		remove_proc_entry("drbd", NULL);

2332
	drbd_genl_unregister();
P
Philipp Reisner 已提交
2333

2334
	down_write(&drbd_cfg_rwsem);
2335
	idr_for_each_entry(&minors, mdev, i)
2336
		drbd_delete_device(mdev);
2337
	up_write(&drbd_cfg_rwsem);
2338

2339
	drbd_destroy_mempools();
P
Philipp Reisner 已提交
2340 2341
	unregister_blkdev(DRBD_MAJOR, "drbd");

2342 2343
	idr_destroy(&minors);

P
Philipp Reisner 已提交
2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360
	printk(KERN_INFO "drbd: module cleanup done.\n");
}

/**
 * drbd_congested() - Callback for pdflush
 * @congested_data:	User data
 * @bdi_bits:		Bits pdflush is currently interested in
 *
 * Returns 1<<BDI_async_congested and/or 1<<BDI_sync_congested if we are congested.
 */
static int drbd_congested(void *congested_data, int bdi_bits)
{
	struct drbd_conf *mdev = congested_data;
	struct request_queue *q;
	char reason = '-';
	int r = 0;

2361
	if (!may_inc_ap_bio(mdev)) {
P
Philipp Reisner 已提交
2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375
		/* DRBD has frozen IO */
		r = bdi_bits;
		reason = 'd';
		goto out;
	}

	if (get_ldev(mdev)) {
		q = bdev_get_queue(mdev->ldev->backing_bdev);
		r = bdi_congested(&q->backing_dev_info, bdi_bits);
		put_ldev(mdev);
		if (r)
			reason = 'b';
	}

2376
	if (bdi_bits & (1 << BDI_async_congested) && test_bit(NET_CONGESTED, &mdev->tconn->flags)) {
P
Philipp Reisner 已提交
2377 2378 2379 2380 2381 2382 2383 2384 2385
		r |= (1 << BDI_async_congested);
		reason = reason == 'b' ? 'a' : 'n';
	}

out:
	mdev->congestion_reason = reason;
	return r;
}

2386 2387 2388 2389 2390 2391 2392
static void drbd_init_workqueue(struct drbd_work_queue* wq)
{
	sema_init(&wq->s, 0);
	spin_lock_init(&wq->q_lock);
	INIT_LIST_HEAD(&wq->q);
}

2393
struct drbd_tconn *conn_get_by_name(const char *name)
2394 2395 2396
{
	struct drbd_tconn *tconn;

2397 2398 2399
	if (!name || !name[0])
		return NULL;

2400
	down_read(&drbd_cfg_rwsem);
2401
	list_for_each_entry(tconn, &drbd_tconns, all_tconn) {
2402 2403
		if (!strcmp(tconn->name, name)) {
			kref_get(&tconn->kref);
2404
			goto found;
2405
		}
2406 2407 2408
	}
	tconn = NULL;
found:
2409
	up_read(&drbd_cfg_rwsem);
2410 2411 2412
	return tconn;
}

2413 2414 2415 2416 2417
static int drbd_alloc_socket(struct drbd_socket *socket)
{
	socket->rbuf = (void *) __get_free_page(GFP_KERNEL);
	if (!socket->rbuf)
		return -ENOMEM;
2418 2419 2420
	socket->sbuf = (void *) __get_free_page(GFP_KERNEL);
	if (!socket->sbuf)
		return -ENOMEM;
2421 2422 2423 2424 2425
	return 0;
}

static void drbd_free_socket(struct drbd_socket *socket)
{
2426
	free_page((unsigned long) socket->sbuf);
2427 2428 2429
	free_page((unsigned long) socket->rbuf);
}

2430 2431
void conn_free_crypto(struct drbd_tconn *tconn)
{
2432 2433 2434 2435
	drbd_free_sock(tconn);

	crypto_free_hash(tconn->csums_tfm);
	crypto_free_hash(tconn->verify_tfm);
2436
	crypto_free_hash(tconn->cram_hmac_tfm);
2437
	crypto_free_hash(tconn->integrity_tfm);
2438
	crypto_free_hash(tconn->peer_integrity_tfm);
2439 2440
	kfree(tconn->int_dig_in);
	kfree(tconn->int_dig_vv);
2441 2442 2443

	tconn->csums_tfm = NULL;
	tconn->verify_tfm = NULL;
2444
	tconn->cram_hmac_tfm = NULL;
2445
	tconn->integrity_tfm = NULL;
2446
	tconn->peer_integrity_tfm = NULL;
2447 2448 2449 2450
	tconn->int_dig_in = NULL;
	tconn->int_dig_vv = NULL;
}

2451
struct drbd_tconn *conn_create(const char *name)
2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462
{
	struct drbd_tconn *tconn;

	tconn = kzalloc(sizeof(struct drbd_tconn), GFP_KERNEL);
	if (!tconn)
		return NULL;

	tconn->name = kstrdup(name, GFP_KERNEL);
	if (!tconn->name)
		goto fail;

2463 2464 2465 2466 2467
	if (drbd_alloc_socket(&tconn->data))
		goto fail;
	if (drbd_alloc_socket(&tconn->meta))
		goto fail;

2468 2469 2470
	if (!zalloc_cpumask_var(&tconn->cpu_mask, GFP_KERNEL))
		goto fail;

2471 2472 2473
	if (!tl_init(tconn))
		goto fail;

2474
	tconn->cstate = C_STANDALONE;
2475
	mutex_init(&tconn->cstate_mutex);
2476
	spin_lock_init(&tconn->req_lock);
2477
	mutex_init(&tconn->conf_update);
2478
	init_waitqueue_head(&tconn->ping_wait);
2479
	idr_init(&tconn->volumes);
2480

2481 2482 2483 2484 2485 2486
	drbd_init_workqueue(&tconn->data.work);
	mutex_init(&tconn->data.mutex);

	drbd_init_workqueue(&tconn->meta.work);
	mutex_init(&tconn->meta.mutex);

2487 2488 2489 2490
	drbd_thread_init(tconn, &tconn->receiver, drbdd_init, "receiver");
	drbd_thread_init(tconn, &tconn->worker, drbd_worker, "worker");
	drbd_thread_init(tconn, &tconn->asender, drbd_asender, "asender");

2491
	drbd_set_res_opts_defaults(&tconn->res_opts);
2492

2493
	down_write(&drbd_cfg_rwsem);
2494
	kref_init(&tconn->kref);
2495
	list_add_tail(&tconn->all_tconn, &drbd_tconns);
2496
	up_write(&drbd_cfg_rwsem);
2497 2498 2499 2500

	return tconn;

fail:
2501
	tl_cleanup(tconn);
2502
	free_cpumask_var(tconn->cpu_mask);
2503 2504
	drbd_free_socket(&tconn->meta);
	drbd_free_socket(&tconn->data);
2505 2506 2507 2508 2509 2510
	kfree(tconn->name);
	kfree(tconn);

	return NULL;
}

2511
void conn_destroy(struct kref *kref)
2512
{
2513 2514
	struct drbd_tconn *tconn = container_of(kref, struct drbd_tconn, kref);

2515
	idr_destroy(&tconn->volumes);
2516

2517
	free_cpumask_var(tconn->cpu_mask);
2518 2519
	drbd_free_socket(&tconn->meta);
	drbd_free_socket(&tconn->data);
2520
	kfree(tconn->name);
2521 2522
	kfree(tconn->int_dig_in);
	kfree(tconn->int_dig_vv);
2523 2524 2525
	kfree(tconn);
}

2526
enum drbd_ret_code conn_new_minor(struct drbd_tconn *tconn, unsigned int minor, int vnr)
P
Philipp Reisner 已提交
2527 2528 2529 2530
{
	struct drbd_conf *mdev;
	struct gendisk *disk;
	struct request_queue *q;
2531
	int vnr_got = vnr;
2532
	int minor_got = minor;
2533
	enum drbd_ret_code err = ERR_NOMEM;
2534 2535 2536 2537

	mdev = minor_to_mdev(minor);
	if (mdev)
		return ERR_MINOR_EXISTS;
P
Philipp Reisner 已提交
2538 2539 2540 2541

	/* GFP_KERNEL, we are outside of all write-out paths */
	mdev = kzalloc(sizeof(struct drbd_conf), GFP_KERNEL);
	if (!mdev)
2542 2543
		return ERR_NOMEM;

2544
	kref_get(&tconn->kref);
2545
	mdev->tconn = tconn;
2546

P
Philipp Reisner 已提交
2547
	mdev->minor = minor;
2548
	mdev->vnr = vnr;
P
Philipp Reisner 已提交
2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562

	drbd_init_set_defaults(mdev);

	q = blk_alloc_queue(GFP_KERNEL);
	if (!q)
		goto out_no_q;
	mdev->rq_queue = q;
	q->queuedata   = mdev;

	disk = alloc_disk(1);
	if (!disk)
		goto out_no_disk;
	mdev->vdisk = disk;

2563
	set_disk_ro(disk, true);
P
Philipp Reisner 已提交
2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575 2576 2577 2578

	disk->queue = q;
	disk->major = DRBD_MAJOR;
	disk->first_minor = minor;
	disk->fops = &drbd_ops;
	sprintf(disk->disk_name, "drbd%d", minor);
	disk->private_data = mdev;

	mdev->this_bdev = bdget(MKDEV(DRBD_MAJOR, minor));
	/* we have no partitions. we contain only ourselves. */
	mdev->this_bdev->bd_contains = mdev->this_bdev;

	q->backing_dev_info.congested_fn = drbd_congested;
	q->backing_dev_info.congested_data = mdev;

2579
	blk_queue_make_request(q, drbd_make_request);
2580 2581 2582
	/* Setting the max_hw_sectors to an odd value of 8kibyte here
	   This triggers a max_bio_size message upon first attach or connect */
	blk_queue_max_hw_sectors(q, DRBD_MAX_BIO_SIZE_SAFE >> 8);
P
Philipp Reisner 已提交
2583 2584
	blk_queue_bounce_limit(q, BLK_BOUNCE_ANY);
	blk_queue_merge_bvec(q, drbd_merge_bvec);
2585
	q->queue_lock = &mdev->tconn->req_lock; /* needed since we use */
P
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2586 2587 2588 2589 2590 2591 2592

	mdev->md_io_page = alloc_page(GFP_KERNEL);
	if (!mdev->md_io_page)
		goto out_no_io_page;

	if (drbd_bm_init(mdev))
		goto out_no_bitmap;
2593
	mdev->read_requests = RB_ROOT;
2594
	mdev->write_requests = RB_ROOT;
P
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2595 2596 2597 2598 2599 2600 2601 2602

	mdev->current_epoch = kzalloc(sizeof(struct drbd_epoch), GFP_KERNEL);
	if (!mdev->current_epoch)
		goto out_no_epoch;

	INIT_LIST_HEAD(&mdev->current_epoch->list);
	mdev->epochs = 1;

2603
	if (!idr_pre_get(&minors, GFP_KERNEL))
2604 2605 2606
		goto out_no_minor_idr;
	if (idr_get_new_above(&minors, mdev, minor, &minor_got))
		goto out_no_minor_idr;
2607
	if (minor_got != minor) {
2608 2609
		err = ERR_MINOR_EXISTS;
		drbd_msg_put_info("requested minor exists already");
2610
		goto out_idr_remove_minor;
2611
	}
2612 2613 2614 2615 2616 2617 2618 2619 2620 2621

	if (!idr_pre_get(&tconn->volumes, GFP_KERNEL))
		goto out_idr_remove_minor;
	if (idr_get_new_above(&tconn->volumes, mdev, vnr, &vnr_got))
		goto out_idr_remove_minor;
	if (vnr_got != vnr) {
		err = ERR_INVALID_REQUEST;
		drbd_msg_put_info("requested volume exists already");
		goto out_idr_remove_vol;
	}
2622 2623
	add_disk(disk);

2624 2625 2626 2627 2628
	/* inherit the connection state */
	mdev->state.conn = tconn->cstate;
	if (mdev->state.conn == C_WF_REPORT_PARAMS)
		drbd_connected(vnr, mdev, tconn);

2629
	return NO_ERROR;
P
Philipp Reisner 已提交
2630

2631 2632
out_idr_remove_vol:
	idr_remove(&tconn->volumes, vnr_got);
2633 2634
out_idr_remove_minor:
	idr_remove(&minors, minor_got);
2635
	synchronize_rcu();
2636
out_no_minor_idr:
2637
	kfree(mdev->current_epoch);
P
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2638 2639 2640 2641 2642 2643 2644 2645 2646 2647
out_no_epoch:
	drbd_bm_cleanup(mdev);
out_no_bitmap:
	__free_page(mdev->md_io_page);
out_no_io_page:
	put_disk(disk);
out_no_disk:
	blk_cleanup_queue(q);
out_no_q:
	kfree(mdev);
2648
	kref_put(&tconn->kref, &conn_destroy);
2649
	return err;
P
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2650 2651 2652 2653 2654 2655
}

int __init drbd_init(void)
{
	int err;

2656
	if (minor_count < DRBD_MINOR_COUNT_MIN || minor_count > DRBD_MINOR_COUNT_MAX) {
P
Philipp Reisner 已提交
2657
		printk(KERN_ERR
2658
		       "drbd: invalid minor_count (%d)\n", minor_count);
P
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2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673
#ifdef MODULE
		return -EINVAL;
#else
		minor_count = 8;
#endif
	}

	err = register_blkdev(DRBD_MAJOR, "drbd");
	if (err) {
		printk(KERN_ERR
		       "drbd: unable to register block device major %d\n",
		       DRBD_MAJOR);
		return err;
	}

2674 2675 2676 2677 2678 2679 2680
	err = drbd_genl_register();
	if (err) {
		printk(KERN_ERR "drbd: unable to register generic netlink family\n");
		goto fail;
	}


P
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2681 2682 2683 2684 2685 2686 2687 2688 2689 2690
	register_reboot_notifier(&drbd_notifier);

	/*
	 * allocate all necessary structs
	 */
	err = -ENOMEM;

	init_waitqueue_head(&drbd_pp_wait);

	drbd_proc = NULL; /* play safe for drbd_cleanup */
2691
	idr_init(&minors);
P
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2692 2693 2694

	err = drbd_create_mempools();
	if (err)
2695
		goto fail;
P
Philipp Reisner 已提交
2696

2697
	drbd_proc = proc_create_data("drbd", S_IFREG | S_IRUGO , NULL, &drbd_proc_fops, NULL);
P
Philipp Reisner 已提交
2698 2699
	if (!drbd_proc)	{
		printk(KERN_ERR "drbd: unable to register proc file\n");
2700
		goto fail;
P
Philipp Reisner 已提交
2701 2702 2703
	}

	rwlock_init(&global_state_lock);
2704
	INIT_LIST_HEAD(&drbd_tconns);
P
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2705 2706 2707 2708 2709 2710 2711 2712 2713 2714

	printk(KERN_INFO "drbd: initialized. "
	       "Version: " REL_VERSION " (api:%d/proto:%d-%d)\n",
	       API_VERSION, PRO_VERSION_MIN, PRO_VERSION_MAX);
	printk(KERN_INFO "drbd: %s\n", drbd_buildtag());
	printk(KERN_INFO "drbd: registered as block device major %d\n",
		DRBD_MAJOR);

	return 0; /* Success! */

2715
fail:
P
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2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729
	drbd_cleanup();
	if (err == -ENOMEM)
		/* currently always the case */
		printk(KERN_ERR "drbd: ran out of memory\n");
	else
		printk(KERN_ERR "drbd: initialization failure\n");
	return err;
}

void drbd_free_bc(struct drbd_backing_dev *ldev)
{
	if (ldev == NULL)
		return;

2730 2731
	blkdev_put(ldev->backing_bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
	blkdev_put(ldev->md_bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
P
Philipp Reisner 已提交
2732 2733 2734 2735

	kfree(ldev);
}

2736 2737 2738 2739 2740 2741 2742 2743
void drbd_free_sock(struct drbd_tconn *tconn)
{
	if (tconn->data.socket) {
		mutex_lock(&tconn->data.mutex);
		kernel_sock_shutdown(tconn->data.socket, SHUT_RDWR);
		sock_release(tconn->data.socket);
		tconn->data.socket = NULL;
		mutex_unlock(&tconn->data.mutex);
P
Philipp Reisner 已提交
2744
	}
2745 2746 2747 2748 2749 2750
	if (tconn->meta.socket) {
		mutex_lock(&tconn->meta.mutex);
		kernel_sock_shutdown(tconn->meta.socket, SHUT_RDWR);
		sock_release(tconn->meta.socket);
		tconn->meta.socket = NULL;
		mutex_unlock(&tconn->meta.mutex);
P
Philipp Reisner 已提交
2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765
	}
}

/* meta data management */

struct meta_data_on_disk {
	u64 la_size;           /* last agreed size. */
	u64 uuid[UI_SIZE];   /* UUIDs. */
	u64 device_uuid;
	u64 reserved_u64_1;
	u32 flags;             /* MDF */
	u32 magic;
	u32 md_size_sect;
	u32 al_offset;         /* offset to this block */
	u32 al_nr_extents;     /* important for restoring the AL */
2766
	      /* `-- act_log->nr_elements <-- ldev->dc.al_extents */
P
Philipp Reisner 已提交
2767 2768
	u32 bm_offset;         /* offset to the bitmap, from here */
	u32 bm_bytes_per_bit;  /* BM_BLOCK_SIZE */
2769 2770
	u32 la_peer_max_bio_size;   /* last peer max_bio_size */
	u32 reserved_u32[3];
P
Philipp Reisner 已提交
2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783

} __packed;

/**
 * drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set
 * @mdev:	DRBD device.
 */
void drbd_md_sync(struct drbd_conf *mdev)
{
	struct meta_data_on_disk *buffer;
	sector_t sector;
	int i;

2784 2785
	del_timer(&mdev->md_sync_timer);
	/* timer may be rearmed by drbd_md_mark_dirty() now. */
P
Philipp Reisner 已提交
2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810
	if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
		return;

	/* We use here D_FAILED and not D_ATTACHING because we try to write
	 * metadata even if we detach due to a disk failure! */
	if (!get_ldev_if_state(mdev, D_FAILED))
		return;

	mutex_lock(&mdev->md_io_mutex);
	buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);
	memset(buffer, 0, 512);

	buffer->la_size = cpu_to_be64(drbd_get_capacity(mdev->this_bdev));
	for (i = UI_CURRENT; i < UI_SIZE; i++)
		buffer->uuid[i] = cpu_to_be64(mdev->ldev->md.uuid[i]);
	buffer->flags = cpu_to_be32(mdev->ldev->md.flags);
	buffer->magic = cpu_to_be32(DRBD_MD_MAGIC);

	buffer->md_size_sect  = cpu_to_be32(mdev->ldev->md.md_size_sect);
	buffer->al_offset     = cpu_to_be32(mdev->ldev->md.al_offset);
	buffer->al_nr_extents = cpu_to_be32(mdev->act_log->nr_elements);
	buffer->bm_bytes_per_bit = cpu_to_be32(BM_BLOCK_SIZE);
	buffer->device_uuid = cpu_to_be64(mdev->ldev->md.device_uuid);

	buffer->bm_offset = cpu_to_be32(mdev->ldev->md.bm_offset);
2811
	buffer->la_peer_max_bio_size = cpu_to_be32(mdev->peer_max_bio_size);
P
Philipp Reisner 已提交
2812 2813 2814 2815

	D_ASSERT(drbd_md_ss__(mdev, mdev->ldev) == mdev->ldev->md.md_offset);
	sector = mdev->ldev->md.md_offset;

2816
	if (drbd_md_sync_page_io(mdev, mdev->ldev, sector, WRITE)) {
P
Philipp Reisner 已提交
2817 2818
		/* this was a try anyways ... */
		dev_err(DEV, "meta data update failed!\n");
2819
		drbd_chk_io_error(mdev, 1, true);
P
Philipp Reisner 已提交
2820 2821 2822 2823 2824 2825 2826 2827 2828 2829 2830 2831 2832 2833 2834
	}

	/* Update mdev->ldev->md.la_size_sect,
	 * since we updated it on metadata. */
	mdev->ldev->md.la_size_sect = drbd_get_capacity(mdev->this_bdev);

	mutex_unlock(&mdev->md_io_mutex);
	put_ldev(mdev);
}

/**
 * drbd_md_read() - Reads in the meta data super block
 * @mdev:	DRBD device.
 * @bdev:	Device from which the meta data should be read in.
 *
2835
 * Return 0 (NO_ERROR) on success, and an enum drbd_ret_code in case
P
Philipp Reisner 已提交
2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848
 * something goes wrong.  Currently only: ERR_IO_MD_DISK, ERR_MD_INVALID.
 */
int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev)
{
	struct meta_data_on_disk *buffer;
	int i, rv = NO_ERROR;

	if (!get_ldev_if_state(mdev, D_ATTACHING))
		return ERR_IO_MD_DISK;

	mutex_lock(&mdev->md_io_mutex);
	buffer = (struct meta_data_on_disk *)page_address(mdev->md_io_page);

2849
	if (drbd_md_sync_page_io(mdev, bdev, bdev->md.md_offset, READ)) {
L
Lucas De Marchi 已提交
2850
		/* NOTE: can't do normal error processing here as this is
P
Philipp Reisner 已提交
2851 2852 2853 2854 2855 2856
		   called BEFORE disk is attached */
		dev_err(DEV, "Error while reading metadata.\n");
		rv = ERR_IO_MD_DISK;
		goto err;
	}

2857
	if (buffer->magic != cpu_to_be32(DRBD_MD_MAGIC)) {
P
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2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891
		dev_err(DEV, "Error while reading metadata, magic not found.\n");
		rv = ERR_MD_INVALID;
		goto err;
	}
	if (be32_to_cpu(buffer->al_offset) != bdev->md.al_offset) {
		dev_err(DEV, "unexpected al_offset: %d (expected %d)\n",
		    be32_to_cpu(buffer->al_offset), bdev->md.al_offset);
		rv = ERR_MD_INVALID;
		goto err;
	}
	if (be32_to_cpu(buffer->bm_offset) != bdev->md.bm_offset) {
		dev_err(DEV, "unexpected bm_offset: %d (expected %d)\n",
		    be32_to_cpu(buffer->bm_offset), bdev->md.bm_offset);
		rv = ERR_MD_INVALID;
		goto err;
	}
	if (be32_to_cpu(buffer->md_size_sect) != bdev->md.md_size_sect) {
		dev_err(DEV, "unexpected md_size: %u (expected %u)\n",
		    be32_to_cpu(buffer->md_size_sect), bdev->md.md_size_sect);
		rv = ERR_MD_INVALID;
		goto err;
	}

	if (be32_to_cpu(buffer->bm_bytes_per_bit) != BM_BLOCK_SIZE) {
		dev_err(DEV, "unexpected bm_bytes_per_bit: %u (expected %u)\n",
		    be32_to_cpu(buffer->bm_bytes_per_bit), BM_BLOCK_SIZE);
		rv = ERR_MD_INVALID;
		goto err;
	}

	bdev->md.la_size_sect = be64_to_cpu(buffer->la_size);
	for (i = UI_CURRENT; i < UI_SIZE; i++)
		bdev->md.uuid[i] = be64_to_cpu(buffer->uuid[i]);
	bdev->md.flags = be32_to_cpu(buffer->flags);
2892
	bdev->dc.al_extents = be32_to_cpu(buffer->al_nr_extents);
P
Philipp Reisner 已提交
2893 2894
	bdev->md.device_uuid = be64_to_cpu(buffer->device_uuid);

2895
	spin_lock_irq(&mdev->tconn->req_lock);
2896 2897 2898 2899 2900 2901
	if (mdev->state.conn < C_CONNECTED) {
		int peer;
		peer = be32_to_cpu(buffer->la_peer_max_bio_size);
		peer = max_t(int, peer, DRBD_MAX_BIO_SIZE_SAFE);
		mdev->peer_max_bio_size = peer;
	}
2902
	spin_unlock_irq(&mdev->tconn->req_lock);
2903

2904 2905
	if (bdev->dc.al_extents < 7)
		bdev->dc.al_extents = 127;
P
Philipp Reisner 已提交
2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921

 err:
	mutex_unlock(&mdev->md_io_mutex);
	put_ldev(mdev);

	return rv;
}

/**
 * drbd_md_mark_dirty() - Mark meta data super block as dirty
 * @mdev:	DRBD device.
 *
 * Call this function if you change anything that should be written to
 * the meta-data super block. This function sets MD_DIRTY, and starts a
 * timer that ensures that within five seconds you have to call drbd_md_sync().
 */
2922
#ifdef DEBUG
2923 2924 2925 2926 2927 2928 2929 2930 2931
void drbd_md_mark_dirty_(struct drbd_conf *mdev, unsigned int line, const char *func)
{
	if (!test_and_set_bit(MD_DIRTY, &mdev->flags)) {
		mod_timer(&mdev->md_sync_timer, jiffies + HZ);
		mdev->last_md_mark_dirty.line = line;
		mdev->last_md_mark_dirty.func = func;
	}
}
#else
P
Philipp Reisner 已提交
2932 2933
void drbd_md_mark_dirty(struct drbd_conf *mdev)
{
2934
	if (!test_and_set_bit(MD_DIRTY, &mdev->flags))
2935
		mod_timer(&mdev->md_sync_timer, jiffies + 5*HZ);
P
Philipp Reisner 已提交
2936
}
2937
#endif
P
Philipp Reisner 已提交
2938 2939 2940 2941 2942

static void drbd_uuid_move_history(struct drbd_conf *mdev) __must_hold(local)
{
	int i;

2943
	for (i = UI_HISTORY_START; i < UI_HISTORY_END; i++)
P
Philipp Reisner 已提交
2944 2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958 2959 2960 2961 2962 2963 2964 2965 2966 2967 2968 2969 2970 2971 2972 2973 2974 2975 2976 2977 2978 2979 2980 2981
		mdev->ldev->md.uuid[i+1] = mdev->ldev->md.uuid[i];
}

void _drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
{
	if (idx == UI_CURRENT) {
		if (mdev->state.role == R_PRIMARY)
			val |= 1;
		else
			val &= ~((u64)1);

		drbd_set_ed_uuid(mdev, val);
	}

	mdev->ldev->md.uuid[idx] = val;
	drbd_md_mark_dirty(mdev);
}


void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local)
{
	if (mdev->ldev->md.uuid[idx]) {
		drbd_uuid_move_history(mdev);
		mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[idx];
	}
	_drbd_uuid_set(mdev, idx, val);
}

/**
 * drbd_uuid_new_current() - Creates a new current UUID
 * @mdev:	DRBD device.
 *
 * Creates a new current UUID, and rotates the old current UUID into
 * the bitmap slot. Causes an incremental resync upon next connect.
 */
void drbd_uuid_new_current(struct drbd_conf *mdev) __must_hold(local)
{
	u64 val;
2982 2983 2984 2985
	unsigned long long bm_uuid = mdev->ldev->md.uuid[UI_BITMAP];

	if (bm_uuid)
		dev_warn(DEV, "bm UUID was already set: %llX\n", bm_uuid);
P
Philipp Reisner 已提交
2986 2987 2988 2989 2990

	mdev->ldev->md.uuid[UI_BITMAP] = mdev->ldev->md.uuid[UI_CURRENT];

	get_random_bytes(&val, sizeof(u64));
	_drbd_uuid_set(mdev, UI_CURRENT, val);
2991
	drbd_print_uuids(mdev, "new current UUID");
2992 2993
	/* get it to stable storage _now_ */
	drbd_md_sync(mdev);
P
Philipp Reisner 已提交
2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005
}

void drbd_uuid_set_bm(struct drbd_conf *mdev, u64 val) __must_hold(local)
{
	if (mdev->ldev->md.uuid[UI_BITMAP] == 0 && val == 0)
		return;

	if (val == 0) {
		drbd_uuid_move_history(mdev);
		mdev->ldev->md.uuid[UI_HISTORY_START] = mdev->ldev->md.uuid[UI_BITMAP];
		mdev->ldev->md.uuid[UI_BITMAP] = 0;
	} else {
3006 3007 3008
		unsigned long long bm_uuid = mdev->ldev->md.uuid[UI_BITMAP];
		if (bm_uuid)
			dev_warn(DEV, "bm UUID was already set: %llX\n", bm_uuid);
P
Philipp Reisner 已提交
3009

3010
		mdev->ldev->md.uuid[UI_BITMAP] = val & ~((u64)1);
P
Philipp Reisner 已提交
3011 3012 3013 3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047 3048 3049 3050 3051 3052
	}
	drbd_md_mark_dirty(mdev);
}

/**
 * drbd_bmio_set_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
 * @mdev:	DRBD device.
 *
 * Sets all bits in the bitmap and writes the whole bitmap to stable storage.
 */
int drbd_bmio_set_n_write(struct drbd_conf *mdev)
{
	int rv = -EIO;

	if (get_ldev_if_state(mdev, D_ATTACHING)) {
		drbd_md_set_flag(mdev, MDF_FULL_SYNC);
		drbd_md_sync(mdev);
		drbd_bm_set_all(mdev);

		rv = drbd_bm_write(mdev);

		if (!rv) {
			drbd_md_clear_flag(mdev, MDF_FULL_SYNC);
			drbd_md_sync(mdev);
		}

		put_ldev(mdev);
	}

	return rv;
}

/**
 * drbd_bmio_clear_n_write() - io_fn for drbd_queue_bitmap_io() or drbd_bitmap_io()
 * @mdev:	DRBD device.
 *
 * Clears all bits in the bitmap and writes the whole bitmap to stable storage.
 */
int drbd_bmio_clear_n_write(struct drbd_conf *mdev)
{
	int rv = -EIO;

3053
	drbd_resume_al(mdev);
P
Philipp Reisner 已提交
3054 3055 3056 3057 3058 3059 3060 3061 3062
	if (get_ldev_if_state(mdev, D_ATTACHING)) {
		drbd_bm_clear_all(mdev);
		rv = drbd_bm_write(mdev);
		put_ldev(mdev);
	}

	return rv;
}

3063
static int w_bitmap_io(struct drbd_work *w, int unused)
P
Philipp Reisner 已提交
3064 3065
{
	struct bm_io_work *work = container_of(w, struct bm_io_work, w);
3066
	struct drbd_conf *mdev = w->mdev;
3067
	int rv = -EIO;
P
Philipp Reisner 已提交
3068 3069 3070

	D_ASSERT(atomic_read(&mdev->ap_bio_cnt) == 0);

3071
	if (get_ldev(mdev)) {
3072
		drbd_bm_lock(mdev, work->why, work->flags);
3073 3074 3075 3076
		rv = work->io_fn(mdev);
		drbd_bm_unlock(mdev);
		put_ldev(mdev);
	}
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3078
	clear_bit_unlock(BITMAP_IO, &mdev->flags);
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3079 3080 3081 3082 3083 3084 3085
	wake_up(&mdev->misc_wait);

	if (work->done)
		work->done(mdev, rv);

	clear_bit(BITMAP_IO_QUEUED, &mdev->flags);
	work->why = NULL;
3086
	work->flags = 0;
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3087

3088
	return 0;
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3089 3090
}

3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101 3102 3103
void drbd_ldev_destroy(struct drbd_conf *mdev)
{
	lc_destroy(mdev->resync);
	mdev->resync = NULL;
	lc_destroy(mdev->act_log);
	mdev->act_log = NULL;
	__no_warn(local,
		drbd_free_bc(mdev->ldev);
		mdev->ldev = NULL;);

	clear_bit(GO_DISKLESS, &mdev->flags);
}

3104
static int w_go_diskless(struct drbd_work *w, int unused)
3105
{
3106 3107
	struct drbd_conf *mdev = w->mdev;

3108
	D_ASSERT(mdev->state.disk == D_FAILED);
3109 3110
	/* we cannot assert local_cnt == 0 here, as get_ldev_if_state will
	 * inc/dec it frequently. Once we are D_DISKLESS, no one will touch
3111 3112
	 * the protected members anymore, though, so once put_ldev reaches zero
	 * again, it will be safe to free them. */
3113
	drbd_force_state(mdev, NS(disk, D_DISKLESS));
3114
	return 0;
3115 3116 3117 3118 3119 3120
}

void drbd_go_diskless(struct drbd_conf *mdev)
{
	D_ASSERT(mdev->state.disk == D_FAILED);
	if (!test_and_set_bit(GO_DISKLESS, &mdev->flags))
3121
		drbd_queue_work(&mdev->tconn->data.work, &mdev->go_diskless);
3122 3123
}

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3124 3125 3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 3136 3137 3138
/**
 * drbd_queue_bitmap_io() - Queues an IO operation on the whole bitmap
 * @mdev:	DRBD device.
 * @io_fn:	IO callback to be called when bitmap IO is possible
 * @done:	callback to be called after the bitmap IO was performed
 * @why:	Descriptive text of the reason for doing the IO
 *
 * While IO on the bitmap happens we freeze application IO thus we ensure
 * that drbd_set_out_of_sync() can not be called. This function MAY ONLY be
 * called from worker context. It MUST NOT be used while a previous such
 * work is still pending!
 */
void drbd_queue_bitmap_io(struct drbd_conf *mdev,
			  int (*io_fn)(struct drbd_conf *),
			  void (*done)(struct drbd_conf *, int),
3139
			  char *why, enum bm_flag flags)
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{
3141
	D_ASSERT(current == mdev->tconn->worker.task);
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3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152

	D_ASSERT(!test_bit(BITMAP_IO_QUEUED, &mdev->flags));
	D_ASSERT(!test_bit(BITMAP_IO, &mdev->flags));
	D_ASSERT(list_empty(&mdev->bm_io_work.w.list));
	if (mdev->bm_io_work.why)
		dev_err(DEV, "FIXME going to queue '%s' but '%s' still pending?\n",
			why, mdev->bm_io_work.why);

	mdev->bm_io_work.io_fn = io_fn;
	mdev->bm_io_work.done = done;
	mdev->bm_io_work.why = why;
3153
	mdev->bm_io_work.flags = flags;
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3154

3155
	spin_lock_irq(&mdev->tconn->req_lock);
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3156 3157
	set_bit(BITMAP_IO, &mdev->flags);
	if (atomic_read(&mdev->ap_bio_cnt) == 0) {
3158
		if (!test_and_set_bit(BITMAP_IO_QUEUED, &mdev->flags))
3159
			drbd_queue_work(&mdev->tconn->data.work, &mdev->bm_io_work.w);
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3160
	}
3161
	spin_unlock_irq(&mdev->tconn->req_lock);
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3162 3163 3164 3165 3166 3167 3168 3169 3170 3171 3172
}

/**
 * drbd_bitmap_io() -  Does an IO operation on the whole bitmap
 * @mdev:	DRBD device.
 * @io_fn:	IO callback to be called when bitmap IO is possible
 * @why:	Descriptive text of the reason for doing the IO
 *
 * freezes application IO while that the actual IO operations runs. This
 * functions MAY NOT be called from worker context.
 */
3173 3174
int drbd_bitmap_io(struct drbd_conf *mdev, int (*io_fn)(struct drbd_conf *),
		char *why, enum bm_flag flags)
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3175 3176 3177
{
	int rv;

3178
	D_ASSERT(current != mdev->tconn->worker.task);
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3179

3180 3181
	if ((flags & BM_LOCKED_SET_ALLOWED) == 0)
		drbd_suspend_io(mdev);
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3182

3183
	drbd_bm_lock(mdev, why, flags);
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3184 3185 3186
	rv = io_fn(mdev);
	drbd_bm_unlock(mdev);

3187 3188
	if ((flags & BM_LOCKED_SET_ALLOWED) == 0)
		drbd_resume_io(mdev);
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3189 3190 3191 3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216

	return rv;
}

void drbd_md_set_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
{
	if ((mdev->ldev->md.flags & flag) != flag) {
		drbd_md_mark_dirty(mdev);
		mdev->ldev->md.flags |= flag;
	}
}

void drbd_md_clear_flag(struct drbd_conf *mdev, int flag) __must_hold(local)
{
	if ((mdev->ldev->md.flags & flag) != 0) {
		drbd_md_mark_dirty(mdev);
		mdev->ldev->md.flags &= ~flag;
	}
}
int drbd_md_test_flag(struct drbd_backing_dev *bdev, int flag)
{
	return (bdev->md.flags & flag) != 0;
}

static void md_sync_timer_fn(unsigned long data)
{
	struct drbd_conf *mdev = (struct drbd_conf *) data;

3217
	drbd_queue_work_front(&mdev->tconn->data.work, &mdev->md_sync_work);
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3218 3219
}

3220
static int w_md_sync(struct drbd_work *w, int unused)
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3221
{
3222 3223
	struct drbd_conf *mdev = w->mdev;

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3224
	dev_warn(DEV, "md_sync_timer expired! Worker calls drbd_md_sync().\n");
3225 3226 3227 3228
#ifdef DEBUG
	dev_warn(DEV, "last md_mark_dirty: %s:%u\n",
		mdev->last_md_mark_dirty.func, mdev->last_md_mark_dirty.line);
#endif
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3229
	drbd_md_sync(mdev);
3230
	return 0;
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3231 3232
}

3233
const char *cmdname(enum drbd_packet cmd)
3234 3235 3236 3237 3238 3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 3261 3262
{
	/* THINK may need to become several global tables
	 * when we want to support more than
	 * one PRO_VERSION */
	static const char *cmdnames[] = {
		[P_DATA]	        = "Data",
		[P_DATA_REPLY]	        = "DataReply",
		[P_RS_DATA_REPLY]	= "RSDataReply",
		[P_BARRIER]	        = "Barrier",
		[P_BITMAP]	        = "ReportBitMap",
		[P_BECOME_SYNC_TARGET]  = "BecomeSyncTarget",
		[P_BECOME_SYNC_SOURCE]  = "BecomeSyncSource",
		[P_UNPLUG_REMOTE]	= "UnplugRemote",
		[P_DATA_REQUEST]	= "DataRequest",
		[P_RS_DATA_REQUEST]     = "RSDataRequest",
		[P_SYNC_PARAM]	        = "SyncParam",
		[P_SYNC_PARAM89]	= "SyncParam89",
		[P_PROTOCOL]            = "ReportProtocol",
		[P_UUIDS]	        = "ReportUUIDs",
		[P_SIZES]	        = "ReportSizes",
		[P_STATE]	        = "ReportState",
		[P_SYNC_UUID]           = "ReportSyncUUID",
		[P_AUTH_CHALLENGE]      = "AuthChallenge",
		[P_AUTH_RESPONSE]	= "AuthResponse",
		[P_PING]		= "Ping",
		[P_PING_ACK]	        = "PingAck",
		[P_RECV_ACK]	        = "RecvAck",
		[P_WRITE_ACK]	        = "WriteAck",
		[P_RS_WRITE_ACK]	= "RSWriteAck",
3263
		[P_DISCARD_WRITE]        = "DiscardWrite",
3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277
		[P_NEG_ACK]	        = "NegAck",
		[P_NEG_DREPLY]	        = "NegDReply",
		[P_NEG_RS_DREPLY]	= "NegRSDReply",
		[P_BARRIER_ACK]	        = "BarrierAck",
		[P_STATE_CHG_REQ]       = "StateChgRequest",
		[P_STATE_CHG_REPLY]     = "StateChgReply",
		[P_OV_REQUEST]          = "OVRequest",
		[P_OV_REPLY]            = "OVReply",
		[P_OV_RESULT]           = "OVResult",
		[P_CSUM_RS_REQUEST]     = "CsumRSRequest",
		[P_RS_IS_IN_SYNC]	= "CsumRSIsInSync",
		[P_COMPRESSED_BITMAP]   = "CBitmap",
		[P_DELAY_PROBE]         = "DelayProbe",
		[P_OUT_OF_SYNC]		= "OutOfSync",
3278
		[P_RETRY_WRITE]		= "RetryWrite",
3279 3280 3281 3282 3283 3284 3285 3286
		[P_RS_CANCEL]		= "RSCancel",
		[P_CONN_ST_CHG_REQ]	= "conn_st_chg_req",
		[P_CONN_ST_CHG_REPLY]	= "conn_st_chg_reply",

		/* enum drbd_packet, but not commands - obsoleted flags:
		 *	P_MAY_IGNORE
		 *	P_MAX_OPT_CMD
		 */
3287 3288
	};

3289
	/* too big for the array: 0xfffX */
3290 3291 3292 3293
	if (cmd == P_INITIAL_META)
		return "InitialMeta";
	if (cmd == P_INITIAL_DATA)
		return "InitialData";
3294 3295
	if (cmd == P_CONNECTION_FEATURES)
		return "ConnectionFeatures";
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Andreas Gruenbacher 已提交
3296
	if (cmd >= ARRAY_SIZE(cmdnames))
3297 3298 3299 3300
		return "Unknown";
	return cmdnames[cmd];
}

3301 3302 3303 3304 3305 3306 3307 3308
/**
 * drbd_wait_misc  -  wait for a request to make progress
 * @mdev:	device associated with the request
 * @i:		the struct drbd_interval embedded in struct drbd_request or
 *		struct drbd_peer_request
 */
int drbd_wait_misc(struct drbd_conf *mdev, struct drbd_interval *i)
{
3309
	struct net_conf *nc;
3310 3311 3312
	DEFINE_WAIT(wait);
	long timeout;

3313 3314 3315 3316
	rcu_read_lock();
	nc = rcu_dereference(mdev->tconn->net_conf);
	if (!nc) {
		rcu_read_unlock();
3317
		return -ETIMEDOUT;
3318 3319 3320
	}
	timeout = nc->ko_count ? nc->timeout * HZ / 10 * nc->ko_count : MAX_SCHEDULE_TIMEOUT;
	rcu_read_unlock();
3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335

	/* Indicate to wake up mdev->misc_wait on progress.  */
	i->waiting = true;
	prepare_to_wait(&mdev->misc_wait, &wait, TASK_INTERRUPTIBLE);
	spin_unlock_irq(&mdev->tconn->req_lock);
	timeout = schedule_timeout(timeout);
	finish_wait(&mdev->misc_wait, &wait);
	spin_lock_irq(&mdev->tconn->req_lock);
	if (!timeout || mdev->state.conn < C_CONNECTED)
		return -ETIMEDOUT;
	if (signal_pending(current))
		return -ERESTARTSYS;
	return 0;
}

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3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355 3356
#ifdef CONFIG_DRBD_FAULT_INJECTION
/* Fault insertion support including random number generator shamelessly
 * stolen from kernel/rcutorture.c */
struct fault_random_state {
	unsigned long state;
	unsigned long count;
};

#define FAULT_RANDOM_MULT 39916801  /* prime */
#define FAULT_RANDOM_ADD	479001701 /* prime */
#define FAULT_RANDOM_REFRESH 10000

/*
 * Crude but fast random-number generator.  Uses a linear congruential
 * generator, with occasional help from get_random_bytes().
 */
static unsigned long
_drbd_fault_random(struct fault_random_state *rsp)
{
	long refresh;

3357
	if (!rsp->count--) {
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Philipp Reisner 已提交
3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376
		get_random_bytes(&refresh, sizeof(refresh));
		rsp->state += refresh;
		rsp->count = FAULT_RANDOM_REFRESH;
	}
	rsp->state = rsp->state * FAULT_RANDOM_MULT + FAULT_RANDOM_ADD;
	return swahw32(rsp->state);
}

static char *
_drbd_fault_str(unsigned int type) {
	static char *_faults[] = {
		[DRBD_FAULT_MD_WR] = "Meta-data write",
		[DRBD_FAULT_MD_RD] = "Meta-data read",
		[DRBD_FAULT_RS_WR] = "Resync write",
		[DRBD_FAULT_RS_RD] = "Resync read",
		[DRBD_FAULT_DT_WR] = "Data write",
		[DRBD_FAULT_DT_RD] = "Data read",
		[DRBD_FAULT_DT_RA] = "Data read ahead",
		[DRBD_FAULT_BM_ALLOC] = "BM allocation",
3377 3378
		[DRBD_FAULT_AL_EE] = "EE allocation",
		[DRBD_FAULT_RECEIVE] = "receive data corruption",
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Philipp Reisner 已提交
3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396
	};

	return (type < DRBD_FAULT_MAX) ? _faults[type] : "**Unknown**";
}

unsigned int
_drbd_insert_fault(struct drbd_conf *mdev, unsigned int type)
{
	static struct fault_random_state rrs = {0, 0};

	unsigned int ret = (
		(fault_devs == 0 ||
			((1 << mdev_to_minor(mdev)) & fault_devs) != 0) &&
		(((_drbd_fault_random(&rrs) % 100) + 1) <= fault_rate));

	if (ret) {
		fault_count++;

3397
		if (__ratelimit(&drbd_ratelimit_state))
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3398 3399 3400 3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425 3426 3427 3428 3429 3430 3431
			dev_warn(DEV, "***Simulating %s failure\n",
				_drbd_fault_str(type));
	}

	return ret;
}
#endif

const char *drbd_buildtag(void)
{
	/* DRBD built from external sources has here a reference to the
	   git hash of the source code. */

	static char buildtag[38] = "\0uilt-in";

	if (buildtag[0] == 0) {
#ifdef CONFIG_MODULES
		if (THIS_MODULE != NULL)
			sprintf(buildtag, "srcversion: %-24s", THIS_MODULE->srcversion);
		else
#endif
			buildtag[0] = 'b';
	}

	return buildtag;
}

module_init(drbd_init)
module_exit(drbd_cleanup)

EXPORT_SYMBOL(drbd_conn_str);
EXPORT_SYMBOL(drbd_role_str);
EXPORT_SYMBOL(drbd_disk_str);
EXPORT_SYMBOL(drbd_set_st_err_str);