path: root/scripts/mod/file2alias.c

/* Simple code to turn various tables in an ELF file into alias definitions.
 * This deals with kernel datastructures where they should be
 * dealt with: in the kernel source.
 *
 * Copyright 2002-2003  Rusty Russell, IBM Corporation
 *           2003       Kai Germaschewski
 *
 *
 * This software may be used and distributed according to the terms
 * of the GNU General Public License, incorporated herein by reference.
 */

#include "modpost.h"
#include "devicetable-offsets.h"

/* We use the ELF typedefs for kernel_ulong_t but bite the bullet and
 * use either stdint.h or inttypes.h for the rest. */
#if KERNEL_ELFCLASS == ELFCLASS32
typedef Elf32_Addr	kernel_ulong_t;
#define BITS_PER_LONG 32
#else
typedef Elf64_Addr	kernel_ulong_t;
#define BITS_PER_LONG 64
#endif
#ifdef __sun__
#include <inttypes.h>
#else
#include <stdint.h>
#endif

#include <ctype.h>
#include <stdbool.h>

typedef uint32_t	__u32;
typedef uint16_t	__u16;
typedef unsigned char	__u8;
typedef struct {
	__u8 b[16];
} guid_t;

/* backwards compatibility, don't use in new code */
typedef struct {
	__u8 b[16];
} uuid_le;
typedef struct {
	__u8 b[16];
} uuid_t;
#define	UUID_STRING_LEN		36

/* Big exception to the "don't include kernel headers into userspace, which
 * even potentially has different endianness and word sizes, since
 * we handle those differences explicitly below */
#include "../../include/linux/mod_devicetable.h"

/* This array collects all instances that use the generic do_table */
struct devtable {
	const char *device_id; /* name of table, __mod_<name>__*_device_table. */
	unsigned long id_size;
	int (*do_entry)(const char *filename, void *symval, char *alias);
};

/* Size of alias provided to do_entry functions */
#define ALIAS_SIZE 500

/* Define a variable f that holds the value of field f of struct devid
 * based at address m.
 */
#define DEF_FIELD(m, devid, f) \
	typeof(((struct devid *)0)->f) f = TO_NATIVE(*(typeof(f) *)((m) + OFF_##devid##_##f))

/* Define a variable v that holds the address of field f of struct devid
 * based at address m.  Due to the way typeof works, for a field of type
 * T[N] the variable has type T(*)[N], _not_ T*.
 */
#define DEF_FIELD_ADDR_VAR(m, devid, f, v) \
	typeof(((struct devid *)0)->f) *v = ((m) + OFF_##devid##_##f)

/* Define a variable f that holds the address of field f of struct devid
 * based at address m.  Due to the way typeof works, for a field of type
 * T[N] the variable has type T(*)[N], _not_ T*.
 */
#define DEF_FIELD_ADDR(m, devid, f) \
	DEF_FIELD_ADDR_VAR(m, devid, f, f)

#define ADD(str, sep, cond, field)                              \
do {                                                            \
        strcat(str, sep);                                       \
        if (cond)                                               \
                sprintf(str + strlen(str),                      \
                        sizeof(field) == 1 ? "%02X" :           \
                        sizeof(field) == 2 ? "%04X" :           \
                        sizeof(field) == 4 ? "%08X" : "",       \
                        field);                                 \
        else                                                    \
                sprintf(str + strlen(str), "*");                \
} while(0)

/* End in a wildcard, for future extension */
static inline void add_wildcard(char *str)
{
	int len = strlen(str);

	if (str[len - 1] != '*')
		strcat(str + len, "*");
}

static inline void add_uuid(char *str, uuid_le uuid)
{
	int len = strlen(str);

	sprintf(str + len, "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
		uuid.b[3], uuid.b[2], uuid.b[1], uuid.b[0],
		uuid.b[5], uuid.b[4], uuid.b[7], uuid.b[6],
		uuid.b[8], uuid.b[9], uuid.b[10], uuid.b[11],
		uuid.b[12], uuid.b[13], uuid.b[14], uuid.b[15]);
}

static inline void add_guid(char *str, guid_t guid)
{
	int len = strlen(str);

	sprintf(str + len, "%02X%02X%02X%02X-%02X%02X-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X",
		guid.b[3], guid.b[2], guid.b[1], guid.b[0],
		guid.b[5], guid.b[4], guid.b[7], guid.b[6],
		guid.b[8], guid.b[9], guid.b[10], guid.b[11],
		guid.b[12], guid.b[13], guid.b[14], guid.b[15]);
}

/**
 * Check that sizeof(device_id type) are consistent with size of section
 * in .o file. If in-consistent then userspace and kernel does not agree
 * on actual size which is a bug.
 * Also verify that the final entry in the table is all zeros.
 * Ignore both checks if build host differ from target host and size differs.
 **/
static void device_id_check(const char *modname, const char *device_id,
			    unsigned long size, unsigned long id_size,
			    void *symval)
{
	int i;

	if (size % id_size || size < id_size) {
		fatal("%s: sizeof(struct %s_device_id)=%lu is not a modulo "
		      "of the size of "
		      "section __mod_%s__<identifier>_device_table=%lu.\n"
		      "Fix definition of struct %s_device_id "
		      "in mod_devicetable.h\n",
		      modname, device_id, id_size, device_id, size, device_id);
	}
	/* Verify last one is a terminator */
	for (i = 0; i < id_size; i++ ) {
		if (*(uint8_t*)(symval+size-id_size+i)) {
			fprintf(stderr,"%s: struct %s_device_id is %lu bytes.  "
				"The last of %lu is:\n",
				modname, devic