/* -*- mode: c; c-basic-offset: 8; -*-
 * vim: noexpandtab sw=8 ts=8 sts=0:
 *
 * heartbeat.c
 *
 * Register ourselves with the heartbaet service, keep our node maps
 * up to date, and fire off recovery when needed.
 *
 * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
 *
 * This program 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 of the License, or (at your option) any later version.
 *
 * This program 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 this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 021110-1307, USA.
 */

#include <linux/fs.h>
#include <linux/types.h>
#include <linux/highmem.h>

#include <cluster/masklog.h>

#include "ocfs2.h"

#include "alloc.h"
#include "heartbeat.h"
#include "inode.h"
#include "journal.h"
#include "ocfs2_trace.h"

#include "buffer_head_io.h"

static inline void __ocfs2_node_map_set_bit(struct ocfs2_node_map *map,
					    int bit);
static inline void __ocfs2_node_map_clear_bit(struct ocfs2_node_map *map,
					      int bit);

/* special case -1 for now
 * TODO: should *really* make sure the calling func never passes -1!!  */
static void ocfs2_node_map_init(struct ocfs2_node_map *map)
{
	map->num_nodes = OCFS2_NODE_MAP_MAX_NODES;
	memset(map->map, 0, BITS_TO_LONGS(OCFS2_NODE_MAP_MAX_NODES) *
	       sizeof(unsigned long));
}

void ocfs2_init_node_maps(struct ocfs2_super *osb)
{
	spin_lock_init(&osb->node_map_lock);
	ocfs2_node_map_init(&osb->osb_recovering_orphan_dirs);
}

void ocfs2_do_node_down(int node_num, void *data)
{
	struct ocfs2_super *osb = data;

	BUG_ON(osb->node_num == node_num);

	trace_ocfs2_do_node_down(node_num);

	if (!osb->cconn) {
		/*
		 * No cluster connection means we're not even ready to
		 * participate yet.  We check the slots after the cluster
		 * comes up, so we will notice the node death then.  We
		 * can safely ignore it here.
		 */
		return;
	}

	ocfs2_recovery_thread(osb, node_num);
}

static inline void __ocfs2_node_map_set_bit(struct ocfs2_node_map *map,
					    int bit)
{
	set_bit(bit, map->map);
}

void ocfs2_node_map_set_bit(struct ocfs2_super *osb,
			    struct ocfs2_node_map *map,
			    int bit)
{
	if (bit==-1)
		return;
	BUG_ON(bit >= map->num_nodes);
	spin_lock(&osb->node_map_lock);
	__ocfs2_node_map_set_bit(map, bit);
	spin_unlock(&osb->node_map_lock);
}

static inline void __ocfs2_node_map_clear_bit(struct ocfs2_node_map *map,
					      int bit)
{
	clear_bit(bit, map->map);
}

void ocfs2_node_map_clear_bit(struct ocfs2_super *osb,
			      struct ocfs2_node_map *map,
			      int bit)
{
	if (bit==-1)
		return;
	BUG_ON(bit >= map->num_nodes);
	spin_lock(&osb->node_map_lock);
	__ocfs2_node_map_clear_bit(map, bit);
	spin_unlock(&osb->node_map_lock);
}

int ocfs2_node_map_test_bit(struct ocfs2_super *osb,
			    struct ocfs2_node_map *map,
			    int bit)
{
	int ret;
	if (bit >= map->num_nodes) {
		mlog(ML_ERROR, "bit=%d map->num_nodes=%d\n", bit, map->num_nodes);
		BUG();
	}
	spin_lock(&osb->node_map_lock);
	ret = test_bit(bit, map->map);
	spin_unlock(&osb->node_map_lock);
	return ret;
}

elect name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Iago Abal &lt;mail@iagoabal.eu&gt;</td><td class='right'>2017-01-11 14:00:21 +0100</td></tr>
<tr><th>committer</th><td>Vinod Koul &lt;vinod.koul@intel.com&gt;</td><td class='right'>2017-01-25 15:35:11 +0530</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/image/mdc800.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>91539eb1fda2d530d3b268eef542c5414e54bf1a</a> (<a href='/cgit.cgi/linux/net-next.git/patch/drivers/usb/image/mdc800.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>960f5ca6342ad20837aff18aad6e8ecd7da32fd6</a> /<a href='/cgit.cgi/linux/net-next.git/tree/drivers/usb/image/mdc800.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>drivers/usb/image/mdc800.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/image/mdc800.c?id=6610d0edf6dc7ee97e46ab3a538a565c79d26199'>6610d0edf6dc7ee97e46ab3a538a565c79d26199</a> (<a href='/cgit.cgi/linux/net-next.git/diff/drivers/usb/image/mdc800.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a&amp;id2=6610d0edf6dc7ee97e46ab3a538a565c79d26199'>diff</a>)</td></tr></table>
<div class='commit-subject'>dmaengine: pl330: fix double lock</div><div class='commit-msg'>The static bug finder EBA (http://www.iagoabal.eu/eba/) reported the
following double-lock bug:

    Double lock:
    1. spin_lock_irqsave(pch-&gt;lock, flags) at pl330_free_chan_resources:2236;
    2. call to function `pl330_release_channel' immediately after;
    3. call to function `dma_pl330_rqcb' in line 1753;
    4. spin_lock_irqsave(pch-&gt;lock, flags) at dma_pl330_rqcb:1505.

I have fixed it as suggested by Marek Szyprowski.

First, I have replaced `pch-&gt;lock' with `pl330-&gt;lock' in functions
`pl330_alloc_chan_resources' and `pl330_free_chan_resources'. This avoids
the double-lock by acquiring a different lock than `dma_pl330_rqcb'.

NOTE that, as a result, `pl330_free_chan_resources' executes
`list_splice_tail_init' on `pch-&gt;work_list' under lock `pl330-&gt;lock',
whereas in the rest of the code `pch-&gt;work_list' is protected by
`pch-&gt;lock'. I don't know if this may cause race conditions. Similarly
`pch-&gt;cyclic' is written by `pl330_alloc_chan_resources' under
`pl330-&gt;lock' but read by `pl330_tx_submit' under `pch-&gt;lock'.

Second, I have removed locking from `pl330_request_channel' and
`pl330_release_channel' functions. Function `pl330_request_channel' is
only called from `pl330_alloc_chan_resources', so the lock is already
held. Function `pl330_release_channel' is called from
`pl330_free_chan_resources', which already holds the lock, and from
`pl330_del'. Function `pl330_del' is called in an error path of
`pl330_probe' and at the end of `pl330_remove', but I assume that there
cannot be concurrent accesses to the protected data at those points.

Signed-off-by: Iago Abal &lt;mail@iagoabal.eu&gt;
Reviewed-by: Marek Szyprowski &lt;m.szyprowski@samsung.com&gt;
Signed-off-by: Vinod Koul &lt;vinod.koul@intel.com&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>Diffstat</a> (limited to 'drivers/usb/image/mdc800.c')</div><table summary='diffstat' class='diffstat'>