#include <linux/gfp.h>
#include <linux/types.h>
#include <linux/radix-tree.h>
#include <linux/rcupdate.h>

struct item {
	unsigned long index;
	unsigned int order;
};

struct item *item_create(unsigned long index, unsigned int order);
int __item_insert(struct radix_tree_root *root, struct item *item);
int item_insert(struct radix_tree_root *root, unsigned long index);
int item_insert_order(struct radix_tree_root *root, unsigned long index,
			unsigned order);
int item_delete(struct radix_tree_root *root, unsigned long index);
struct item *item_lookup(struct radix_tree_root *root, unsigned long index);

void item_check_present(struct radix_tree_root *root, unsigned long index);
void item_check_absent(struct radix_tree_root *root, unsigned long index);
void item_gang_check_present(struct radix_tree_root *root,
			unsigned long start, unsigned long nr,
			int chunk, int hop);
void item_full_scan(struct radix_tree_root *root, unsigned long start,
			unsigned long nr, int chunk);
void item_kill_tree(struct radix_tree_root *root);

int tag_tagged_items(struct radix_tree_root *, pthread_mutex_t *,
			unsigned long start, unsigned long end, unsigned batch,
			unsigned iftag, unsigned thentag);
unsigned long find_item(struct radix_tree_root *, void *item);

void tag_check(void);
void multiorder_checks(void);
void iteration_test(unsigned order, unsigned duration);
void benchmark(void);

struct item *
item_tag_set(struct radix_tree_root *root, unsigned long index, int tag);
struct item *
item_tag_clear(struct radix_tree_root *root, unsigned long index, int tag);
int item_tag_get(struct radix_tree_root *root, unsigned long index, int tag);
void tree_verify_min_height(struct radix_tree_root *root, int maxindex);
void verify_tag_consistency(struct radix_tree_root *root, unsigned int tag);

extern int nr_allocated;

/* Normally private parts of lib/radix-tree.c */
struct radix_tree_node *entry_to_node(void *ptr);
void radix_tree_dump(struct radix_tree_root *root);
int root_tag_get(struct radix_tree_root *root, unsigned int tag);
unsigned long node_maxindex(struct radix_tree_node *);
unsigned long shift_maxindex(unsigned int shift);
int radix_tree_cpu_dead(unsigned int cpu);
struct radix_tree_preload {
	unsigned nr;
	struct radix_tree_node *nodes;
};
extern struct radix_tree_preload radix_tree_preloads;
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<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/commit/?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>root</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>drivers</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>usb</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/chipidea?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>chipidea</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/chipidea/Makefile?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>Makefile</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='91539eb1fda2d530d3b268eef542c5414e54bf1a'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select 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/chipidea/Makefile?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>91539eb1fda2d530d3b268eef542c5414e54bf1a</a> (<a href='/cgit.cgi/linux/net-next.git/patch/drivers/usb/chipidea/Makefile?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/chipidea/Makefile?id=91539eb1fda2d530d3b268eef542c5414e54bf1a'>drivers/usb/chipidea/Makefile</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/chipidea/Makefile?id=6610d0edf6dc7ee97e46ab3a538a565c79d26199'>6610d0edf6dc7ee97e46ab3a538a565c79d26199</a> (<a href='/cgit.cgi/linux/net-next.git/diff/drivers/usb/chipidea/Makefile?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/chipidea/Makefile')</div><table summary='diffstat' class='diffstat'>