release/src/router/busybox/util-linux/fstrim.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * fstrim.c - discard the part (or whole) of mounted filesystem.
   4  *
   5  * 03 March 2012 - Malek Degachi <malek-degachi@laposte.net>
   6  * Adapted for busybox from util-linux-2.12a.
   7  *
   8  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   9  */
  10
  11 //config:config FSTRIM
  12 //config:       bool "fstrim"
  13 //config:       default y
  14 //config:       select PLATFORM_LINUX
  15 //config:       help
  16 //config:         Discard unused blocks on a mounted filesystem.
  17
  18 //applet:IF_FSTRIM(APPLET(fstrim, BB_DIR_SBIN, BB_SUID_DROP))
  19
  20 //kbuild:lib-$(CONFIG_FSTRIM) += fstrim.o
  21
  22 //usage:#define fstrim_trivial_usage
  23 //usage:       "[OPTIONS] MOUNTPOINT"
  24 //usage:#define fstrim_full_usage "\n\n"
  25 //usage:        IF_LONG_OPTS(
  26 //usage:       "        -o,--offset=OFFSET      Offset in bytes to discard from"
  27 //usage:     "\n        -l,--length=LEN         Bytes to discard"
  28 //usage:     "\n        -m,--minimum=MIN        Minimum extent length"
  29 //usage:     "\n        -v,--verbose            Print number of discarded bytes"
  30 //usage:        )
  31 //usage:        IF_NOT_LONG_OPTS(
  32 //usage:       "        -o OFFSET       Offset in bytes to discard from"
  33 //usage:     "\n        -l LEN          Bytes to discard"
  34 //usage:     "\n        -m MIN          Minimum extent length"
  35 //usage:     "\n        -v              Print number of discarded bytes"
  36 //usage:        )
  37
  38 #include "libbb.h"
  39 #include <linux/fs.h>
  40
  41 #ifndef FITRIM
  42 struct fstrim_range {
  43         uint64_t start;
  44         uint64_t len;
  45         uint64_t minlen;
  46 };
  47 #define FITRIM          _IOWR('X', 121, struct fstrim_range)
  48 #endif
  49
  50 static const struct suffix_mult fstrim_sfx[] = {
  51         { "KiB", 1024 },
  52         { "kiB", 1024 },
  53         { "K", 1024 },
  54         { "k", 1024 },
  55         { "MiB", 1048576 },
  56         { "miB", 1048576 },
  57         { "M", 1048576 },
  58         { "m", 1048576 },
  59         { "GiB", 1073741824 },
  60         { "giB", 1073741824 },
  61         { "G", 1073741824 },
  62         { "g", 1073741824 },
  63         { "KB", 1000 },
  64         { "MB", 1000000 },
  65         { "GB", 1000000000 },
  66         { "", 0 }
  67 };
  68
  69 int fstrim_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  70 int fstrim_main(int argc UNUSED_PARAM, char **argv)
  71 {
  72         struct fstrim_range range;
  73         char *arg_o, *arg_l, *arg_m, *mp;
  74         unsigned opts;
  75         int fd;
  76
  77         enum {
  78                 OPT_o = (1 << 0),
  79                 OPT_l = (1 << 1),
  80                 OPT_m = (1 << 2),
  81                 OPT_v = (1 << 3),
  82         };
  83
  84 #if ENABLE_LONG_OPTS
  85         static const char getopt_longopts[] ALIGN1 =
  86                 "offset\0"    Required_argument    "o"
  87                 "length\0"    Required_argument    "l"
  88                 "minimum\0"   Required_argument    "m"
  89                 "verbose\0"   No_argument          "v"
  90                 ;
  91         applet_long_options = getopt_longopts;
  92 #endif
  93
  94         opt_complementary = "=1"; /* exactly one non-option arg: the mountpoint */
  95         opts = getopt32(argv, "o:l:m:v", &arg_o, &arg_l, &arg_m);
  96
  97         memset(&range, 0, sizeof(range));
  98         range.len = ULLONG_MAX;
  99
 100         if (opts & OPT_o)
 101                 range.start = xatoull_sfx(arg_o, fstrim_sfx);
 102         if (opts & OPT_l)
 103                 range.len = xatoull_sfx(arg_l, fstrim_sfx);
 104         if (opts & OPT_m)
 105                 range.minlen = xatoull_sfx(arg_m, fstrim_sfx);
 106
 107         mp = argv[optind];
 108         if (find_block_device(mp)) {
 109                 fd = xopen_nonblocking(mp);
 110                 xioctl(fd, FITRIM, &range);
 111                 if (ENABLE_FEATURE_CLEAN_UP)
 112                         close(fd);
 113
 114                 if (opts & OPT_v)
 115                         printf("%s: %llu bytes trimmed\n", mp, (unsigned long long)range.len);
 116                 return EXIT_SUCCESS;
 117         }
 118         return EXIT_FAILURE;
 119 }