/*
 * Derived from arch/ppc/mm/extable.c and arch/i386/mm/extable.c.
 *
 * Copyright (C) 2004 Paul Mackerras, IBM Corp.
 *
 * 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.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/sort.h>
#include <linux/uaccess.h>

#ifndef ARCH_HAS_RELATIVE_EXTABLE
#define ex_to_insn(x)	((x)->insn)
#else
static inline unsigned long ex_to_insn(const struct exception_table_entry *x)
{
	return (unsigned long)&x->insn + x->insn;
}
#endif

#ifndef ARCH_HAS_SORT_EXTABLE
#ifndef ARCH_HAS_RELATIVE_EXTABLE
#define swap_ex		NULL
#else
static void swap_ex(void *a, void *b, int size)
{
	struct exception_table_entry *x = a, *y = b, tmp;
	int delta = b - a;

	tmp = *x;
	x->insn = y->insn + delta;
	y->insn = tmp.insn - delta;

#ifdef swap_ex_entry_fixup
	swap_ex_entry_fixup(x, y, tmp, delta);
#else
	x->fixup = y->fixup + delta;
	y->fixup = tmp.fixup - delta;
#endif
}
#endif /* ARCH_HAS_RELATIVE_EXTABLE */

/*
 * The exception table needs to be sorted so that the binary
 * search that we use to find entries in it works properly.
 * This is used both for the kernel exception table and for
 * the exception tables of modules that get loaded.
 */
static int cmp_ex(const void *a, const void *b)
{
	const struct exception_table_entry *x = a, *y = b;

	/* avoid overflow */
	if (ex_to_insn(x) > ex_to_insn(y))
		return 1;
	if (ex_to_insn(x) < ex_to_insn(y))
		return -1;
	return 0;
}

void sort_extable(struct exception_table_entry *start,
		  struct exception_table_entry *finish)
{
	sort(start, finish - start, sizeof(struct exception_table_entry),
	     cmp_ex, swap_ex);
}

#ifdef CONFIG_MODULES
/*
 * If the exception table is sorted, any referring to the module init
 * will be at the beginning or the end.
 */
void trim_init_extable(struct module *m)
{
	/*trim the beginning*/
	while (m->num_exentries &&
	       within_module_init(ex_to_insn(&m->extable[0]), m)) {
		m->extable++;
		m->num_exentries--;
	}
	/*trim the end*/
	while (m->num_exentries &&
	       within_module_init(ex_to_insn(&m->extable[m->num_exentries - 1]),
				  m))
		m->num_exentries--;
}
#endif /* CONFIG_MODULES */
#endif /* !ARCH_HAS_SORT_EXTABLE */

#ifndef ARCH_HAS_SEARCH_EXTABLE
/*
 * Search one exception table for an entry corresponding to the
 * given instruction address, and return the address of the entry,
 * or NULL if none is found.
 * We use a binary search, and thus we assume that the table is
 * already sorted.
 */
const struct exception_table_entry *
search_extable(const struct exception_table_entry *first,
	       const struct exception_table_entry *last,
	       unsigned long value)
{
	while (first <= last) {
		const struct exception_table_entry *mid;

		mid = ((last - first) >> 1) + first;
		/*
		 * careful, the distance between value and insn
		 * can be larger than MAX_LONG:
		 */
		if (ex_to_insn(mid) < value)
			first = mid + 1;
		else if (ex_to_insn(mid) > value)
			last = mid - 1;
		else
			return mid;
	}
	return NULL;
}
#endif
b25b64b6c1f4b'>bridge: fdb: converge fdb_delete_by functions into one</a></td><td>Nikolay Aleksandrov</td><td>1</td><td><span class='deletions'>-47</span>/<span class='insertions'>+15</span></td></tr>
<tr><td><span title='2017-02-14 12:41:03 -0500'>2017-02-14</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=410b3d48f5111a28bb8d4c3d3dc5984c1baf7fc9'>bridge: fdb: add proper lock checks in searching functions</a></td><td>Nikolay Aleksandrov</td><td>2</td><td><span class='deletions'>-0</span>/<span class='insertions'>+13</span></td></tr>
<tr><td><span title='2017-02-14 12:41:02 -0500'>2017-02-14</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=bfd0aeac52f74bfb44c0974131e44abb33a13e78'>bridge: fdb: converge fdb searching functions into one</a></td><td>Nikolay Aleksandrov</td><td>4</td><td><span class='deletions'>-70</span>/<span class='insertions'>+54</span></td></tr>
<tr><td><span title='2017-02-14 11:44:14 -0500'>2017-02-14</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=d7cf52c249d7aa797ea27808e1526604309ec142'>sched: Fix accidental removal of errout goto</a></td><td>Jiri Pirko</td><td>1</td><td><span class='deletions'>-0</span>/<span class='insertions'>+1</span></td></tr>
<tr><td><span title='2017-02-13 22:23:39 -0500'>2017-02-13</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=37fabbf4d489cc2e1cbf7cde816d9453a65ddfb7'>net: busy-poll: remove LL_FLUSH_FAILED and LL_FLUSH_BUSY</a></td><td>Eric Dumazet</td><td>1</td><td><span class='deletions'>-3</span>/<span class='insertions'>+0</span></td></tr>
<tr><td><span title='2017-02-12 22:11:43 -0500'>2017-02-12</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=7c92d61eca453d5007669e4322dd8e469d443d04'>Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next</a></td><td>David S. Miller</td><td>11</td><td><span class='deletions'>-112</span>/<span class='insertions'>+778</span></td></tr>
<tr><td><span title='2017-02-12 14:45:14 +0100'>2017-02-12</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=7286ff7fde9f963736c7e575572899d8e16b06b7'>netfilter: nf_tables: honor NFT_SET_OBJECT in set backend selection</a></td><td>Pablo Neira Ayuso</td><td>3</td><td><span class='deletions'>-3</span>/<span class='insertions'>+4</span></td></tr>
<tr><td><span title='2017-02-12 14:45:13 +0100'>2017-02-12</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=1a94e38d254b3622d5d53f74b3b716b0fcab0ba8'>netfilter: nf_tables: add NFTA_RULE_ID attribute</a></td><td>Pablo Neira Ayuso</td><td>1</td><td><span class='deletions'>-0</span>/<span class='insertions'>+26</span></td></tr>
<tr><td><span title='2017-02-12 14:45:12 +0100'>2017-02-12</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=74e8bcd21c40dbbb3d74fa904536f8a3bddafed3'>netfilter: nf_tables: add check_genid to the nfnetlink subsystem</a></td><td>Pablo Neira Ayuso</td><td>1</td><td><span class='deletions'>-0</span>/<span class='insertions'>+6</span></td></tr>
<tr><td><span title='2017-02-12 14:45:11 +0100'>2017-02-12</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=8c4d4e8b5626fec965fd5034e5bd5e57790f243f'>netfilter: nfnetlink: allow to check for generation ID</a></td><td>Pablo Neira Ayuso</td><td>1</td><td><span class='deletions'>-4</span>/<span class='insertions'>+27</span></td></tr>
<tr><td><span title='2017-02-12 14:45:10 +0100'>2017-02-12</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=48656835c0405aa2e6c0d6a4305c77b70758d168'>netfilter: nfnetlink: add nfnetlink_rcv_skb_batch()</a></td><td>Pablo Neira Ayuso</td><td>1</td><td><span class='deletions'>-23</span>/<span class='insertions'>+28</span></td></tr>
<tr><td><span title='2017-02-12 14:45:09 +0100'>2017-02-12</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=b745d0358db44ebcef31478314436d6d4ff93bfa'>netfilter: nfnetlink: get rid of u_intX_t types</a></td><td>Pablo Neira Ayuso</td><td>1</td><td><span class='deletions'>-8</span>/<span class='insertions'>+8</span></td></tr>
<tr><td><span title='2017-02-12 14:44:08 +0100'>2017-02-12</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=4dee62b1b9b43c9bbf49c93cd114e1bf1334fb6a'>netfilter: nf_ct_expect: nf_ct_expect_insert() returns void</a></td><td>Gao Feng</td><td>1</td><td><span class='deletions'>-5</span>/<span class='insertions'>+3</span></td></tr>
<tr><td><span title='2017-02-12 14:39:06 +0100'>2017-02-12</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=a96e66e702bc615f5927b15c739c91d5098dac59'>netfilter: nf_ct_sip: Use mod_timer_pending()</a></td><td>Gao Feng</td><td>1</td><td><span class='deletions'>-7</span>/<span class='insertions'>+5</span></td></tr>
<tr><td><span title='2017-02-11 21:38:58 -0500'>2017-02-11</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=87b60cfacf9f17cf71933c6e33b66e68160af71d'>net_sched: fix error recovery at qdisc creation</a></td><td>Eric Dumazet</td><td>5</td><td><span class='deletions'>-23</span>/<span class='insertions'>+19</span></td></tr>
<tr><td><span title='2017-02-11 21:25:18 -0500'>2017-02-11</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=c16ec18599c8c1722d476011786fd9e2529888f7'>net: rename dst_neigh_output back to neigh_output</a></td><td>Julian Anastasov</td><td>2</td><td><span class='deletions'>-2</span>/<span class='insertions'>+2</span></td></tr>
<tr><td><span title='2017-02-11 02:31:11 -0500'>2017-02-11</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net?id=35eeacf1820a08305c2b0960febfa190f5a6dd63'>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net</a></td><td>David S. Miller