common/dmdelay

   1 ##/bin/bash
   2 # SPDX-License-Identifier: GPL-2.0
   3 # Copyright (c) 2016 Red Hat, Inc.  All Rights Reserved.
   4 #
   5 # common functions for setting up and tearing down a dmdelay device
   6
   7 DELAY_NONE=0
   8 DELAY_READ=1
   9
  10 _init_delay()
  11 {
  12         local BLK_DEV_SIZE=`blockdev --getsz $SCRATCH_DEV`
  13         DELAY_DEV=/dev/mapper/delay-test
  14         DELAY_TABLE="0 $BLK_DEV_SIZE delay $SCRATCH_DEV 0 0"
  15         DELAY_TABLE_RDELAY="0 $BLK_DEV_SIZE delay $SCRATCH_DEV 0 10000 $SCRATCH_DEV 0 0"
  16         _dmsetup_create delay-test --table "$DELAY_TABLE" || \
  17                 _fatal "failed to create delay device"
  18 }
  19
  20 _mount_delay()
  21 {
  22         _scratch_options mount
  23         $MOUNT_PROG -t $FSTYP `_common_dev_mount_options` $SCRATCH_OPTIONS \
  24                 $DELAY_DEV $SCRATCH_MNT
  25 }
  26
  27 _unmount_delay()
  28 {
  29         $UMOUNT_PROG $SCRATCH_MNT
  30 }
  31
  32 _cleanup_delay()
  33 {
  34         # If dmsetup load fails then we need to make sure to do resume here
  35         # otherwise the umount will hang
  36         $DMSETUP_PROG resume delay-test > /dev/null 2>&1
  37         $UMOUNT_PROG $SCRATCH_MNT > /dev/null 2>&1
  38         _dmsetup_remove delay-test
  39 }
  40
  41 # _load_delay_table <table> [lockfs]
  42 #
  43 # This defaults to --nolockfs, which doesn't freeze_fs() before loading the new
  44 # table
  45 _load_delay_table()
  46 {
  47         table="$DELAY_TABLE"
  48         [ $1 -eq $DELAY_READ ] && table="$DELAY_TABLE_RDELAY"
  49
  50         suspend_opt="--nolockfs"
  51         [ $# -gt 1 ] && [ $2 -eq 1 ] && suspend_opt=""
  52
  53         # run a suspend/resume cycle to avoid excessive resume delays once a
  54         # delay is introduced below
  55         $DMSETUP_PROG suspend $suspend_opt delay-test
  56         $DMSETUP_PROG resume $suspend_opt delay-test
  57
  58         $DMSETUP_PROG suspend $suspend_opt delay-test
  59         [ $? -ne 0 ] && _fatal "failed to suspend delay-test"
  60
  61         $DMSETUP_PROG load delay-test --table "$table"
  62         [ $? -ne 0 ] && _fatal "failed to load table into delay-test"
  63
  64         $DMSETUP_PROG resume delay-test
  65         [ $? -ne 0 ] && _fatal  "failed to resume delay-test"
  66 }