/*
 * Minimal BPF JIT image disassembler
 *
 * Disassembles BPF JIT compiler emitted opcodes back to asm insn's for
 * debugging or verification purposes.
 *
 * There is no Makefile. Compile with
 *
 *   `gcc -Wall -O2 bpf_jit_disasm.c -o bpf_jit_disasm -lopcodes -lbfd -ldl`
 *
 * or similar.
 *
 * To get the disassembly of the JIT code, do the following:
 *
 *  1) `echo 2 > /proc/sys/net/core/bpf_jit_enable`
 *  2) Load a BPF filter (e.g. `tcpdump -p -n -s 0 -i eth1 host 192.168.20.0/24`)
 *  3) Run e.g. `bpf_jit_disasm -o` to read out the last JIT code
 *
 * Copyright 2013 Daniel Borkmann <borkmann@redhat.com>
 * Licensed under the GNU General Public License, version 2.0 (GPLv2)
 *
 * Note: this is part of the Linux kernel and can be found under tools/net/.
 */

#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <unistd.h>
#include <string.h>
#include <bfd.h>
#include <dis-asm.h>
#include <sys/klog.h>
#include <sys/types.h>
#include <regex.h>

static void get_exec_path(char *tpath, size_t size)
{
	char *path;
	ssize_t len;

	snprintf(tpath, size, "/proc/%d/exe", (int) getpid());
	tpath[size - 1] = 0;

	path = strdup(tpath);
	assert(path);

	len = readlink(path, tpath, size);
	tpath[len] = 0;

	free(path);
}

static void get_asm_insns(uint8_t *image, size_t len, unsigned long base,
			  int opcodes)
{
	int count, i, pc = 0;
	char tpath[256];
	struct disassemble_info info;
	disassembler_ftype disassemble;
	bfd *bfdf;

	memset(tpath, 0, sizeof(tpath));
	get_exec_path(tpath, sizeof(tpath));

	bfdf = bfd_openr(tpath, NULL);
	assert(bfdf);
	assert(bfd_check_format(bfdf, bfd_object));

	init_disassemble_info(&info, stdout, (fprintf_ftype) fprintf);
	info.arch = bfd_get_arch(bfdf);
	info.mach = bfd_get_mach(bfdf);
	info.buffer = image;
	info.buffer_length = len;

	disassemble_init_for_target(&info);

	disassemble = disassembler(bfdf);
	assert(disassemble);

	do {
		printf("%4x:\t", pc);

		count = disassemble(pc, &info);

		if (opcodes) {
			printf("\n\t");
			for (i = 0; i < count; ++i)
				printf("%02x ", (uint8_t) image[pc + i]);
		}
		printf("\n");

		pc += count;
	} while(count > 0 && pc < len);

	bfd_close(bfdf);
}

static char *get_klog_buff(int *klen)
{
	int ret, len = klogctl(10, NULL, 0);
	char *buff = malloc(len);

	assert(buff && klen);
	ret = klogctl(3, buff, len);
	assert(ret >= 0);
	*klen = ret;

	return buff;
}

static void put_klog_buff(char *buff)
{
	free(buff);
}

static int get_last_jit_image(char *haystack, size_t hlen,
			      uint8_t *image, size_t ilen,
			      unsigned long *base)
{
	char *ptr, *pptr, *tmp;
	off_t off = 0;
	int ret, flen, proglen, pass, ulen = 0;
	regmatch_t pmatch[1];
	regex_t regex;

	if (hlen == 0)
		return 0;

	ret = regcomp(&regex, "flen=[[:alnum:]]+ proglen=[[:digit:]]+ "
		      "pass=[[:digit:]]+ image=[[:xdigit:]]+", REG_EXTENDED);
	assert(ret == 0);

	ptr = haystack;
	while (1) {
		ret = regexec(&regex, ptr, 1, pmatch, 0);
		if (ret == 0) {
			ptr += pmatch[0].rm_eo;
			off += pmatch[0].rm_eo;
			assert(off < hlen);
		} else
			break;
	}

	ptr = haystack + off - (pmatch[0].rm_eo - pmatch[0].rm_so);
	ret = sscanf(ptr, "flen=%d proglen=%d pass=%d image=%lx",
		     &flen, &proglen, &pass, base);
	if (ret != 4)
		return 0;

	tmp = ptr = haystack + off;
	while ((ptr = strtok(tmp, "\n")) != NULL && ulen < ilen) {
		tmp = NULL;
		if (!strstr(ptr, "JIT code"))
			continue;
		pptr = ptr;
		while ((ptr = strstr(pptr, ":")))
			pptr = ptr + 1;
		ptr = pptr;
		do {
			image[ulen++] = (uint8_t) strtoul(pptr, &pptr, 16);
			if (ptr == pptr || ulen >= ilen) {
				ulen--;
				break;
			}
			ptr = pptr;
		} while (1);
	}

	assert(ulen == proglen);
	printf("%d bytes emitted from JIT compiler (pass:%d, flen:%d)\n",
	       proglen, pass, flen);
	printf("%lx + <x>:\n", *base);

	regfree(&regex);
	return ulen;
}

int main(int argc, char **argv)
{
	int len, klen, opcodes = 0;
	char *kbuff;
	unsigned long base;
	uint8_t image[4096];

	if (argc > 1) {
		if (!strncmp("-o", argv[argc - 1], 2)) {
			opcodes = 1;
		} else {
			printf("usage: bpf_jit_disasm [-o: show opcodes]\n");
			exit(0);
		}
	}

	bfd_init();
	memset(image, 0, sizeof(image));

	kbuff = get_klog_buff(&klen);

	len = get_last_jit_image(kbuff, klen, image, sizeof(image), &base);
	if (len > 0 && base > 0)
		get_asm_insns(image, len, base, opcodes);

	put_klog_buff(kbuff);

	return 0;
}
</th><td>Mark Brown &lt;broonie@kernel.org&gt;</td><td class='right'>2016-08-04 22:00:21 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?h=nds-private-remove&amp;id=5d764912a0ee6db83e962c1501b5b9e58ba14e15'>5d764912a0ee6db83e962c1501b5b9e58ba14e15</a> (<a href='/cgit.cgi/linux/net-next.git/patch/?id=5d764912a0ee6db83e962c1501b5b9e58ba14e15'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=5d764912a0ee6db83e962c1501b5b9e58ba14e15'>f2bac4fd3a8c6e92f2094ce85904df35fba8c2a9</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?h=nds-private-remove&amp;id=e7ca8fcd15049b1e48ae2ef1434a68a51ef0ead5'>e7ca8fcd15049b1e48ae2ef1434a68a51ef0ead5</a> (<a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=5d764912a0ee6db83e962c1501b5b9e58ba14e15&amp;id2=e7ca8fcd15049b1e48ae2ef1434a68a51ef0ead5'>diff</a>)</td></tr></table>
<div class='commit-subject'>ASoC: da7213: Default to 64 BCLKs per WCLK to support all formats</div><div class='commit-msg'>Previously code defaulted to 32 BCLKS per WCLK which meant 24 and
32 bit DAI formats would not work properly. This patch fixes the
issue by defaulting to 64 BCLKs per WCLK.

Signed-off-by: Adam Thomson &lt;Adam.Thomson.Opensource@diasemi.com&gt;
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=5d764912a0ee6db83e962c1501b5b9e58ba14e15'>Diffstat</a></div><table summary='diffstat' class='diffstat'>