LXR busybox/miscutils/flash_lock

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * Ported to busybox from mtd-utils.
   4 *
   5 * Licensed under GPLv2, see file LICENSE in this source tree.
   6 */
   7//config:config FLASH_LOCK
   8//config:       bool "flash_lock (2.1 kb)"
   9//config:       default n  # doesn't build on Ubuntu 8.04
  10//config:       help
  11//config:       The flash_lock binary from mtd-utils as of git head 5ec0c10d0. This
  12//config:       utility locks part or all of the flash device.
  13//config:
  14//config:config FLASH_UNLOCK
  15//config:       bool "flash_unlock (1.3 kb)"
  16//config:       default n  # doesn't build on Ubuntu 8.04
  17//config:       help
  18//config:       The flash_unlock binary from mtd-utils as of git head 5ec0c10d0. This
  19//config:       utility unlocks part or all of the flash device.
  20
  21//                       APPLET_ODDNAME:name          main               location         suid_type     help
  22//applet:IF_FLASH_LOCK(  APPLET_ODDNAME(flash_lock,   flash_lock_unlock, BB_DIR_USR_SBIN, BB_SUID_DROP, flash_lock))
  23//applet:IF_FLASH_UNLOCK(APPLET_ODDNAME(flash_unlock, flash_lock_unlock, BB_DIR_USR_SBIN, BB_SUID_DROP, flash_unlock))
  24/* not NOEXEC: if flash operation stalls, use less memory in "hung" process */
  25
  26//kbuild:lib-$(CONFIG_FLASH_LOCK) += flash_lock_unlock.o
  27//kbuild:lib-$(CONFIG_FLASH_UNLOCK) += flash_lock_unlock.o
  28
  29//usage:#define flash_lock_trivial_usage
  30//usage:       "MTD_DEVICE OFFSET SECTORS"
  31//usage:#define flash_lock_full_usage "\n\n"
  32//usage:       "Lock part or all of an MTD device. If SECTORS is -1, then all sectors\n"
  33//usage:       "will be locked, regardless of the value of OFFSET"
  34//usage:
  35//usage:#define flash_unlock_trivial_usage
  36//usage:       "MTD_DEVICE"
  37//usage:#define flash_unlock_full_usage "\n\n"
  38//usage:       "Unlock an MTD device"
  39
  40#include "libbb.h"
  41#include <mtd/mtd-user.h>
  42
  43int flash_lock_unlock_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  44int flash_lock_unlock_main(int argc UNUSED_PARAM, char **argv)
  45{
  46        /* note: fields in these structs are 32-bits.
  47         * apparently we can't win anything by using off_t
  48         * or long long's for offset and/or sectors vars. */
  49        struct mtd_info_user info;
  50        struct erase_info_user lock;
  51        unsigned long offset;
  52        long sectors;
  53        int fd;
  54
  55#define do_lock (ENABLE_FLASH_LOCK && (!ENABLE_FLASH_UNLOCK || (applet_name[6] == 'l')))
  56
  57        if (!argv[1])
  58                bb_show_usage();
  59
  60        /* parse offset and number of sectors to lock */
  61        offset = 0;
  62        sectors = -1;
  63        if (do_lock) {
  64                if (!argv[2] || !argv[3])
  65                        bb_show_usage();
  66                offset = xstrtoul(argv[2], 0);
  67                sectors = xstrtol(argv[3], 0);
  68        }
  69
  70        fd = xopen(argv[1], O_RDWR);
  71
  72        xioctl(fd, MEMGETINFO, &info);
  73
  74        lock.start = 0;
  75        lock.length = info.size;
  76        if (do_lock) {
  77                unsigned long size = info.size - info.erasesize;
  78                if (offset > size) {
  79                        bb_error_msg_and_die("%lx is beyond device size %lx\n",
  80                                        offset, size);
  81                }
  82
  83                if (sectors == -1) {
  84                        sectors = info.size / info.erasesize;
  85                } else {
  86// isn't this useless?
  87                        unsigned long num = info.size / info.erasesize;
  88                        if (sectors > num) {
  89                                bb_error_msg_and_die("%ld are too many "
  90                                                "sectors, device only has "
  91                                                "%ld\n", sectors, num);
  92                        }
  93                }
  94
  95                lock.start = offset;
  96                lock.length = sectors * info.erasesize;
  97                xioctl(fd, MEMLOCK, &lock);
  98        } else {
  99                xioctl(fd, MEMUNLOCK, &lock);
 100        }
 101
 102        return EXIT_SUCCESS;
 103}
 104