#ifndef __SOUND_HWDEP_H
#define __SOUND_HWDEP_H

/*
 *  Hardware dependent layer 
 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
 *
 *
 *   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  02111-1307 USA
 *
 */

#include <sound/asound.h>
#include <linux/poll.h>

struct snd_hwdep;

/* hwdep file ops; all ops can be NULL */
struct snd_hwdep_ops {
	long long (*llseek)(struct snd_hwdep *hw, struct file *file,
			    long long offset, int orig);
	long (*read)(struct snd_hwdep *hw, char __user *buf,
		     long count, loff_t *offset);
	long (*write)(struct snd_hwdep *hw, const char __user *buf,
		      long count, loff_t *offset);
	int (*open)(struct snd_hwdep *hw, struct file * file);
	int (*release)(struct snd_hwdep *hw, struct file * file);
	unsigned int (*poll)(struct snd_hwdep *hw, struct file *file,
			     poll_table *wait);
	int (*ioctl)(struct snd_hwdep *hw, struct file *file,
		     unsigned int cmd, unsigned long arg);
	int (*ioctl_compat)(struct snd_hwdep *hw, struct file *file,
			    unsigned int cmd, unsigned long arg);
	int (*mmap)(struct snd_hwdep *hw, struct file *file,
		    struct vm_area_struct *vma);
	int (*dsp_status)(struct snd_hwdep *hw,
			  struct snd_hwdep_dsp_status *status);
	int (*dsp_load)(struct snd_hwdep *hw,
			struct snd_hwdep_dsp_image *image);
};

struct snd_hwdep {
	struct snd_card *card;
	struct list_head list;
	int device;
	char id[32];
	char name[80];
	int iface;

#ifdef CONFIG_SND_OSSEMUL
	int oss_type;
	int ossreg;
#endif

	struct snd_hwdep_ops ops;
	wait_queue_head_t open_wait;
	void *private_data;
	void (*private_free) (struct snd_hwdep *hwdep);
	struct device dev;

	struct mutex open_mutex;
	int used;			/* reference counter */
	unsigned int dsp_loaded;	/* bit fields of loaded dsp indices */
	unsigned int exclusive:1;	/* exclusive access mode */
};

extern int snd_hwdep_new(struct snd_card *card, char *id, int device,
			 struct snd_hwdep **rhwdep);

#endif /* __SOUND_HWDEP_H */
/?id=51ce8bd4d17a761e1a90a34a1b5c9b762cce7553'>root</a>/<a href='/cgit.cgi/linux/net-next.git/log/net?id=51ce8bd4d17a761e1a90a34a1b5c9b762cce7553'>net</a>/<a href='/cgit.cgi/linux/net-next.git/log/net/ipv4?id=51ce8bd4d17a761e1a90a34a1b5c9b762cce7553'>ipv4</a>/<a href='/cgit.cgi/linux/net-next.git/log/net/ipv4/igmp.c?id=51ce8bd4d17a761e1a90a34a1b5c9b762cce7553'>igmp.c</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/cgit.cgi/linux/net-next.git/log/net/ipv4/igmp.c?id=51ce8bd4d17a761e1a90a34a1b5c9b762cce7553&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th><th class='left'>Files</th><th class='left'>Lines</th></tr>
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/net/core/utils.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>91539eb1fda2d530d3b268eef542c5414e54bf1a</a> (<a href='/cgit.cgi/linux/net-next.git/patch/net/core/utils.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/net/core/utils.c?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>net/core/utils.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/core/utils.c?id=6610d0edf6dc7ee97e46ab3a538a565c79d26199'>6610d0edf6dc7ee97e46ab3a538a565c79d26199</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/core/utils.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 'net/core/utils.c')</div><table summary='diffstat' class='diffstat'>