flash_lock, flash_unlock: new applets

By Thierry Reding (thierry.reding AT avionic-design.de)

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

3 files changed, 86 insertions, 1 deletions

diff --git a/miscutils/Config.in b/miscutils/Config.in
index 7feaf4a87..06ff51a7c 100644
--- a/miscutils/Config.in
+++ b/miscutils/Config.in
@@ -250,6 +250,20 @@ config FBSPLASH
             "NN" (ASCII decimal number) - percentage to show on progress bar
             "exit" - well you guessed it
 
+config FLASH_LOCK
+        bool "flash_lock"
+        default n
+        help
+          The flash_lock binary from mtd-utils as of git head 5ec0c10d0. This
+          utility locks part or all of the flash device.
+
+config FLASH_UNLOCK
+        bool "flash_unlock"
+        default n
+        help
+          The flash_unlock binary from mtd-utils as of git head 5ec0c10d0. This
+          utility unlocks part or all of the flash device.
+
 config FLASH_ERASEALL
         bool "flash_eraseall"
         default n
diff --git a/miscutils/Kbuild b/miscutils/Kbuild
index 23d7d8d49..8ae8a488a 100644
--- a/miscutils/Kbuild
+++ b/miscutils/Kbuild
@@ -16,7 +16,9 @@ lib-$(CONFIG_DEVFSD)      += devfsd.o
 lib-$(CONFIG_DEVMEM)      += devmem.o
 lib-$(CONFIG_EJECT)       += eject.o
 lib-$(CONFIG_FBSPLASH)    += fbsplash.o
-lib-$(CONFIG_FLASH_ERASEALL)    += flash_eraseall.o
+lib-$(CONFIG_FLASH_ERASEALL) += flash_eraseall.o
+lib-$(CONFIG_FLASH_LOCK)     += flash_lock_unlock.o
+lib-$(CONFIG_FLASH_UNLOCK)   += flash_lock_unlock.o
 lib-$(CONFIG_IONICE)      += ionice.o
 lib-$(CONFIG_HDPARM)      += hdparm.o
 lib-$(CONFIG_INOTIFYD)    += inotifyd.o
diff --git a/miscutils/flash_lock_unlock.c b/miscutils/flash_lock_unlock.c
new file mode 100644
index 000000000..f4e2f73b2
--- /dev/null
+++ b/miscutils/flash_lock_unlock.c
@@ -0,0 +1,69 @@
+/* vi: set sw=4 ts=4: */
+/* Ported to busybox from mtd-utils.
+ *
+ * Licensed under GPLv2, see file LICENSE in this tarball for details.
+ */
+#include "libbb.h"
+#include <mtd/mtd-user.h>
+
+int flash_lock_unlock_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int flash_lock_unlock_main(int argc UNUSED_PARAM, char **argv)
+{
+        /* note: fields in these structs are 32-bits.
+         * apparently we can't win anything by using off_t
+         * or long long's for offset and/or sectors vars. */
+        struct mtd_info_user info;
+        struct erase_info_user lock;
+        unsigned long offset;
+        long sectors;
+        int fd;
+
+#define do_lock (ENABLE_FLASH_LOCK && (!ENABLE_FLASH_UNLOCK || (applet_name[6] == 'l')))
+
+        if (!argv[1])
+                bb_show_usage();
+
+        /* parse offset and number of sectors to lock */
+        offset = 0;
+        sectors = -1;
+        if (do_lock) {
+                if (!argv[2] || !argv[3])
+                        bb_show_usage();
+                offset = xstrtoul(argv[2], 0);
+                sectors = xstrtol(argv[3], 0);
+        }
+
+        fd = xopen(argv[1], O_RDWR);
+
+        xioctl(fd, MEMGETINFO, &info);
+
+        lock.start = 0;
+        lock.length = info.size;
+        if (do_lock) {
+                unsigned long size = info.size - info.erasesize;
+                if (offset > size) {
+                        bb_error_msg_and_die("%lx is beyond device size %lx\n",
+                                        offset, size);
+                }
+
+                if (sectors == -1) {
+                        sectors = info.size / info.erasesize;
+                } else {
+// isn't this useless?
+                        unsigned long num = info.size / info.erasesize;
+                        if (sectors > num) {
+                                bb_error_msg_and_die("%ld are too many "
+                                                "sectors, device only has "
+                                                "%ld\n", sectors, num);
+                        }
+                }
+
+                lock.start = offset;
+                lock.length = sectors * info.erasesize;
+                xioctl(fd, MEMLOCK, &lock);
+        } else {
+                xioctl(fd, MEMUNLOCK, &lock);
+        }
+
+        return EXIT_SUCCESS;
+}