[GitHub/mt8127/android_kernel_alcatel_ttab.git] / scripts / sortextable.c

/*
 * sortextable.c: Sort the kernel's exception table
 *
 * Copyright 2011 Cavium, Inc.
 *
 * Based on code taken from recortmcount.c which is:
 *
 * Copyright 2009 John F. Reiser <jreiser@BitWagon.com>.  All rights reserved.
 * Licensed under the GNU General Public License, version 2 (GPLv2).
 *
 * Restructured to fit Linux format, as well as other updates:
 *  Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc.
 */

/*
 * Strategy: alter the vmlinux file in-place.
 */

#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <getopt.h>
#include <elf.h>
#include <fcntl.h>
#include <setjmp.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

static int fd_map;	/* File descriptor for file being modified. */
static int mmap_failed; /* Boolean flag. */
static void *ehdr_curr; /* current ElfXX_Ehdr *  for resource cleanup */
static struct stat sb;	/* Remember .st_size, etc. */
static jmp_buf jmpenv;	/* setjmp/longjmp per-file error escape */

/* setjmp() return values */
enum {
	SJ_SETJMP = 0,  /* hardwired first return */
	SJ_FAIL,
	SJ_SUCCEED
};

/* Per-file resource cleanup when multiple files. */
static void
cleanup(void)
{
	if (!mmap_failed)
		munmap(ehdr_curr, sb.st_size);
	close(fd_map);
}

static void __attribute__((noreturn))
fail_file(void)
{
	cleanup();
	longjmp(jmpenv, SJ_FAIL);
}

static void __attribute__((noreturn))
succeed_file(void)
{
	cleanup();
	longjmp(jmpenv, SJ_SUCCEED);
}


/*
 * Get the whole file as a programming convenience in order to avoid
 * malloc+lseek+read+free of many pieces.  If successful, then mmap
 * avoids copying unused pieces; else just read the whole file.
 * Open for both read and write.
 */
static void *mmap_file(char const *fname)
{
	void *addr;

	fd_map = open(fname, O_RDWR);
	if (fd_map < 0 || fstat(fd_map, &sb) < 0) {
		perror(fname);
		fail_file();
	}
	if (!S_ISREG(sb.st_mode)) {
		fprintf(stderr, "not a regular file: %s\n", fname);
		fail_file();
	}
	addr = mmap(0, sb.st_size, PROT_READ|PROT_WRITE, MAP_SHARED,
		    fd_map, 0);
	if (addr == MAP_FAILED) {
		mmap_failed = 1;
		fprintf(stderr, "Could not mmap file: %s\n", fname);
		fail_file();
	}
	return addr;
}

/* w8rev, w8nat, ...: Handle endianness. */

static uint64_t w8rev(uint64_t const x)
{
	return   ((0xff & (x >> (0 * 8))) << (7 * 8))
	       | ((0xff & (x >> (1 * 8))) << (6 * 8))
	       | ((0xff & (x >> (2 * 8))) << (5 * 8))
	       | ((0xff & (x >> (3 * 8))) << (4 * 8))
	       | ((0xff & (x >> (4 * 8))) << (3 * 8))
	       | ((0xff & (x >> (5 * 8))) << (2 * 8))
	       | ((0xff & (x >> (6 * 8))) << (1 * 8))
	       | ((0xff & (x >> (7 * 8))) << (0 * 8));
}

static uint32_t w4rev(uint32_t const x)
{
	return   ((0xff & (x >> (0 * 8))) << (3 * 8))
	       | ((0xff & (x >> (1 * 8))) << (2 * 8))
	       | ((0xff & (x >> (2 * 8))) << (1 * 8))
	       | ((0xff & (x >> (3 * 8))) << (0 * 8));
}

static uint32_t w2rev(uint16_t const x)
{
	return   ((0xff & (x >> (0 * 8))) << (1 * 8))
	       | ((0xff & (x >> (1 * 8))) << (0 * 8));
}

static uint64_t w8nat(uint64_t const x)
{
	return x;
}

static uint32_t w4nat(uint32_t const x)
{
	return x;
}

static uint32_t w2nat(uint16_t const x)
{
	return x;
}

static uint64_t (*w8)(uint64_t);
static uint32_t (*w)(uint32_t);
static uint32_t (*w2)(uint16_t);


/* 32 bit and 64 bit are very similar */
#include "sortextable.h"
#define SORTEXTABLE_64
#include "sortextable.h"


static void
do_file(char const *const fname)
{
	Elf32_Ehdr *const ehdr = mmap_file(fname);

	ehdr_curr = ehdr;
	w = w4nat;
	w2 = w2nat;
	w8 = w8nat;
	switch (ehdr->e_ident[EI_DATA]) {
		static unsigned int const endian = 1;
	default:
		fprintf(stderr, "unrecognized ELF data encoding %d: %s\n",
			ehdr->e_ident[EI_DATA], fname);
		fail_file();
		break;
	case ELFDATA2LSB:
		if (*(unsigned char const *)&endian != 1) {
			/* main() is big endian, file.o is little endian. */
			w = w4rev;
			w2 = w2rev;
			w8 = w8rev;
		}
		break;
	case ELFDATA2MSB:
		if (*(unsigned char const *)&endian != 0) {
			/* main() is little endian, file.o is big endian. */
			w = w4rev;
			w2 = w2rev;
			w8 = w8rev;
		}
		break;
	}  /* end switch */
	if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0
	||  w2(ehdr->e_type) != ET_EXEC
	||  ehdr->e_ident[EI_VERSION] != EV_CURRENT) {
		fprintf(stderr, "unrecognized ET_EXEC file %s\n", fname);
		fail_file();
	}

	switch (w2(ehdr->e_machine)) {
	default:
		fprintf(stderr, "unrecognized e_machine %d %s\n",
			w2(ehdr->e_machine), fname);
		fail_file();
		break;
	case EM_386:
	case EM_MIPS:
	case EM_X86_64:
		break;
	}  /* end switch */

	switch (ehdr->e_ident[EI_CLASS]) {
	default:
		fprintf(stderr, "unrecognized ELF class %d %s\n",
			ehdr->e_ident[EI_CLASS], fname);
		fail_file();
		break;
	case ELFCLASS32:
		if (w2(ehdr->e_ehsize) != sizeof(Elf32_Ehdr)
		||  w2(ehdr->e_shentsize) != sizeof(Elf32_Shdr)) {
			fprintf(stderr,
				"unrecognized ET_EXEC file: %s\n", fname);
			fail_file();
		}
		do32(ehdr, fname);
		break;
	case ELFCLASS64: {
		Elf64_Ehdr *const ghdr = (Elf64_Ehdr *)ehdr;
		if (w2(ghdr->e_ehsize) != sizeof(Elf64_Ehdr)
		||  w2(ghdr->e_shentsize) != sizeof(Elf64_Shdr)) {
			fprintf(stderr,
				"unrecognized ET_EXEC file: %s\n", fname);
			fail_file();
		}
		do64(ghdr, fname);
		break;
	}
	}  /* end switch */

	cleanup();
}

int
main(int argc, char *argv[])
{
	int n_error = 0;  /* gcc-4.3.0 false positive complaint */
	int i;

	if (argc < 2) {
		fprintf(stderr, "usage: sortextable vmlinux...\n");
		return 0;
	}

	/* Process each file in turn, allowing deep failure. */
	for (i = 1; i < argc; i++) {
		char *file = argv[i];
		int const sjval = setjmp(jmpenv);

		switch (sjval) {
		default:
			fprintf(stderr, "internal error: %s\n", file);
			exit(1);
			break;
		case SJ_SETJMP:    /* normal sequence */
			/* Avoid problems if early cleanup() */
			fd_map = -1;
			ehdr_curr = NULL;
			mmap_failed = 1;
			do_file(file);
			break;
		case SJ_FAIL:    /* error in do_file or below */
			++n_error;
			break;
		case SJ_SUCCEED:    /* premature success */
			/* do nothing */
			break;
		}  /* end switch */
	}
	return !!n_error;
}
Commit	Line	Data
a79f248b DD	1	/*
	2	* sortextable.c: Sort the kernel's exception table
	3	*
	4	* Copyright 2011 Cavium, Inc.
	5	*
	6	* Based on code taken from recortmcount.c which is:
	7	*
	8	* Copyright 2009 John F. Reiser <jreiser@BitWagon.com>. All rights reserved.
	9	* Licensed under the GNU General Public License, version 2 (GPLv2).
	10	*
	11	* Restructured to fit Linux format, as well as other updates:
	12	* Copyright 2010 Steven Rostedt <srostedt@redhat.com>, Red Hat Inc.
	13	*/
	14
	15	/*
	16	* Strategy: alter the vmlinux file in-place.
	17	*/
	18
	19	#include <sys/types.h>
	20	#include <sys/mman.h>
	21	#include <sys/stat.h>
	22	#include <getopt.h>
	23	#include <elf.h>
	24	#include <fcntl.h>
	25	#include <setjmp.h>
	26	#include <stdio.h>
	27	#include <stdlib.h>
	28	#include <string.h>
	29	#include <unistd.h>
	30
	31	static int fd_map; /* File descriptor for file being modified. */
	32	static int mmap_failed; /* Boolean flag. */
	33	static void ehdr_curr; / current ElfXX_Ehdr * for resource cleanup */
	34	static struct stat sb; /* Remember .st_size, etc. */
	35	static jmp_buf jmpenv; /* setjmp/longjmp per-file error escape */
	36
	37	/* setjmp() return values */
	38	enum {
	39	SJ_SETJMP = 0, /* hardwired first return */
	40	SJ_FAIL,
	41	SJ_SUCCEED
	42	};
	43
	44	/* Per-file resource cleanup when multiple files. */
	45	static void
	46	cleanup(void)
	47	{
	48	if (!mmap_failed)
	49	munmap(ehdr_curr, sb.st_size);
	50	close(fd_map);
	51	}
	52
	53	static void __attribute__((noreturn))
	54	fail_file(void)
	55	{
	56	cleanup();
	57	longjmp(jmpenv, SJ_FAIL);
	58	}
	59
	60	static void __attribute__((noreturn))
	61	succeed_file(void)
	62	{
	63	cleanup();
	64	longjmp(jmpenv, SJ_SUCCEED);
65	}
66
67
68	/*
69	* Get the whole file as a programming convenience in order to avoid
70	* malloc+lseek+read+free of many pieces. If successful, then mmap
71	* avoids copying unused pieces; else just read the whole file.
72	* Open for both read and write.
73	*/
74	static void mmap_file(char const fname)
75	{
76	void *addr;
77
78	fd_map = open(fname, O_RDWR);
79	if (fd_map < 0 \|\| fstat(fd_map, &sb) < 0) {
80	perror(fname);
81	fail_file();
82	}
83	if (!S_ISREG(sb.st_mode)) {
84	fprintf(stderr, "not a regular file: %s\n", fname);
85	fail_file();
86	}
87	addr = mmap(0, sb.st_size, PROT_READ\|PROT_WRITE, MAP_SHARED,
88	fd_map, 0);
89	if (addr == MAP_FAILED) {
90	mmap_failed = 1;
91	fprintf(stderr, "Could not mmap file: %s\n", fname);
92	fail_file();
93	}
94	return addr;
95	}
96
97	/* w8rev, w8nat, ...: Handle endianness. */
98
99	static uint64_t w8rev(uint64_t const x)
100	{
101	return ((0xff & (x >> (0 * 8))) << (7 * 8))
102	\| ((0xff & (x >> (1 * 8))) << (6 * 8))
103	\| ((0xff & (x >> (2 * 8))) << (5 * 8))
104	\| ((0xff & (x >> (3 * 8))) << (4 * 8))
105	\| ((0xff & (x >> (4 * 8))) << (3 * 8))
106	\| ((0xff & (x >> (5 * 8))) << (2 * 8))
107	\| ((0xff & (x >> (6 * 8))) << (1 * 8))
108	\| ((0xff & (x >> (7 * 8))) << (0 * 8));
109	}
110
111	static uint32_t w4rev(uint32_t const x)
112	{
113	return ((0xff & (x >> (0 * 8))) << (3 * 8))
114	\| ((0xff & (x >> (1 * 8))) << (2 * 8))
115	\| ((0xff & (x >> (2 * 8))) << (1 * 8))
116	\| ((0xff & (x >> (3 * 8))) << (0 * 8));
117	}
118
119	static uint32_t w2rev(uint16_t const x)
120	{
121	return ((0xff & (x >> (0 * 8))) << (1 * 8))
122	\| ((0xff & (x >> (1 * 8))) << (0 * 8));
123	}
124
125	static uint64_t w8nat(uint64_t const x)
126	{
127	return x;
128	}
129
130	static uint32_t w4nat(uint32_t const x)
131	{
132	return x;
133	}
134
135	static uint32_t w2nat(uint16_t const x)
136	{
137	return x;
138	}
139
140	static uint64_t (*w8)(uint64_t);
141	static uint32_t (*w)(uint32_t);
142	static uint32_t (*w2)(uint16_t);
143
144
145	/* 32 bit and 64 bit are very similar */
146	#include "sortextable.h"
147	#define SORTEXTABLE_64
148	#include "sortextable.h"
149
150
151	static void
152	do_file(char const *const fname)
153	{
154	Elf32_Ehdr *const ehdr = mmap_file(fname);
155
156	ehdr_curr = ehdr;
157	w = w4nat;
158	w2 = w2nat;
159	w8 = w8nat;
160	switch (ehdr->e_ident[EI_DATA]) {
161	static unsigned int const endian = 1;
162	default:
163	fprintf(stderr, "unrecognized ELF data encoding %d: %s\n",
164	ehdr->e_ident[EI_DATA], fname);
165	fail_file();
166	break;
167	case ELFDATA2LSB:
168	if ((unsigned char const )&endian != 1) {
169	/* main() is big endian, file.o is little endian. */
170	w = w4rev;
171	w2 = w2rev;
172	w8 = w8rev;
173	}
174	break;
175	case ELFDATA2MSB:
176	if ((unsigned char const )&endian != 0) {
177	/* main() is little endian, file.o is big endian. */
178	w = w4rev;
179	w2 = w2rev;
180	w8 = w8rev;
181	}
182	break;
183	} /* end switch */
184	if (memcmp(ELFMAG, ehdr->e_ident, SELFMAG) != 0
185	\|\| w2(ehdr->e_type) != ET_EXEC
186	\|\| ehdr->e_ident[EI_VERSION] != EV_CURRENT) {
187	fprintf(stderr, "unrecognized ET_EXEC file %s\n", fname);
188	fail_file();
189	}
190
191	switch (w2(ehdr->e_machine)) {
192	default:
193	fprintf(stderr, "unrecognized e_machine %d %s\n",
194	w2(ehdr->e_machine), fname);
195	fail_file();
196	break;
197	case EM_386:
198	case EM_MIPS:
199	case EM_X86_64:
200	break;
201	} /* end switch */
202
203	switch (ehdr->e_ident[EI_CLASS]) {
204	default:
205	fprintf(stderr, "unrecognized ELF class %d %s\n",
206	ehdr->e_ident[EI_CLASS], fname);
207	fail_file();
208	break;
209	case ELFCLASS32:
210	if (w2(ehdr->e_ehsize) != sizeof(Elf32_Ehdr)
211	\|\| w2(ehdr->e_shentsize) != sizeof(Elf32_Shdr)) {
212	fprintf(stderr,
213	"unrecognized ET_EXEC file: %s\n", fname);
214	fail_file();
215	}
216	do32(ehdr, fname);
217	break;
218	case ELFCLASS64: {
219	Elf64_Ehdr const ghdr = (Elf64_Ehdr )ehdr;
220	if (w2(ghdr->e_ehsize) != sizeof(Elf64_Ehdr)
221	\|\| w2(ghdr->e_shentsize) != sizeof(Elf64_Shdr)) {
222	fprintf(stderr,
223	"unrecognized ET_EXEC file: %s\n", fname);
224	fail_file();
225	}
226	do64(ghdr, fname);
227	break;
228	}
229	} /* end switch */
230
231	cleanup();
232	}
233
234	int
235	main(int argc, char *argv[])
236	{
237	int n_error = 0; /* gcc-4.3.0 false positive complaint */
238	int i;
239
240	if (argc < 2) {
241	fprintf(stderr, "usage: sortextable vmlinux...\n");
242	return 0;
243	}
244
245	/* Process each file in turn, allowing deep failure. */
246	for (i = 1; i < argc; i++) {
247	char *file = argv[i];
248	int const sjval = setjmp(jmpenv);
249
250	switch (sjval) {
251	default:
252	fprintf(stderr, "internal error: %s\n", file);
253	exit(1);
254	break;
255	case SJ_SETJMP: /* normal sequence */
256	/* Avoid problems if early cleanup() */
257	fd_map = -1;
258	ehdr_curr = NULL;
259	mmap_failed = 1;
260	do_file(file);
261	break;
262	case SJ_FAIL: /* error in do_file or below */
263	++n_error;
264	break;
265	case SJ_SUCCEED: /* premature success */
266	/* do nothing */
267	break;
268	} /* end switch */
269	}
270	return !!n_error;
271	}