io/sync_file_range.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2012 Red Hat, Inc.
   4  * All Rights Reserved.
   5  */
   6
   7 #include "command.h"
   8 #include "input.h"
   9 #include "init.h"
  10 #include "io.h"
  11
  12 static cmdinfo_t sync_range_cmd;
  13
  14 static void
  15 sync_range_help(void)
  16 {
  17         printf(_(
  18 "\n"
  19 " Trigger specific writeback commands on a range of the current file\n"
  20 "\n"
  21 " With no options, the SYNC_FILE_RANGE_WRITE is implied.\n"
  22 " -a -- wait for IO to finish after writing (SYNC_FILE_RANGE_WAIT_AFTER).\n"
  23 " -b -- wait for IO to finish before writing (SYNC_FILE_RANGE_WAIT_BEFORE).\n"
  24 " -w -- write dirty data in range (SYNC_FILE_RANGE_WRITE).\n"
  25 "\n"));
  26 }
  27
  28 static int
  29 sync_range_f(
  30         int             argc,
  31         char            **argv)
  32 {
  33         off64_t         offset = 0, length = 0;
  34         int             c, sync_mode = 0;
  35         size_t          blocksize, sectsize;
  36
  37         while ((c = getopt(argc, argv, "abw")) != EOF) {
  38                 switch (c) {
  39                 case 'a':
  40                         sync_mode = SYNC_FILE_RANGE_WAIT_AFTER;
  41                         break;
  42                 case 'b':
  43                         sync_mode = SYNC_FILE_RANGE_WAIT_BEFORE;
  44                         break;
  45                 case 'w':
  46                         sync_mode = SYNC_FILE_RANGE_WRITE;
  47                         break;
  48                 default:
  49                         return command_usage(&sync_range_cmd);
  50                 }
  51         }
  52
  53         /* default to just starting writeback on the range */
  54         if (!sync_mode)
  55                 sync_mode = SYNC_FILE_RANGE_WRITE;
  56
  57         if (optind != argc - 2)
  58                 return command_usage(&sync_range_cmd);
  59         init_cvtnum(&blocksize, &sectsize);
  60         offset = cvtnum(blocksize, sectsize, argv[optind]);
  61         if (offset < 0) {
  62                 printf(_("non-numeric offset argument -- %s\n"),
  63                         argv[optind]);
  64                 return 0;
  65         }
  66         optind++;
  67         length = cvtnum(blocksize, sectsize, argv[optind]);
  68         if (length < 0) {
  69                 printf(_("non-numeric length argument -- %s\n"),
  70                         argv[optind]);
  71                 return 0;
  72         }
  73
  74         if (sync_file_range(file->fd, offset, length, sync_mode) < 0) {
  75                 perror("sync_file_range");
  76                 return 0;
  77         }
  78         return 0;
  79 }
  80
  81 void
  82 sync_range_init(void)
  83 {
  84         sync_range_cmd.name = "sync_range";
  85         sync_range_cmd.cfunc = sync_range_f;
  86         sync_range_cmd.argmin = 2;
  87         sync_range_cmd.argmax = -1;
  88         sync_range_cmd.flags = CMD_NOMAP_OK | CMD_FOREIGN_OK;
  89         sync_range_cmd.args = _("[-abw] off len");
  90         sync_range_cmd.oneline = _("Control writeback on a range of a file");
  91         sync_range_cmd.help = sync_range_help;
  92
  93         add_command(&sync_range_cmd);
  94 }