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3# Copyright (c) 2017 Spectra Logic Corporation
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30#
31# $FreeBSD$
32#
33
34#
35# Routines that use gnop(8) to simulate devices that can disappear at any time
36#
37
38# Create a gnop device on top of a real device.  Don't use the full extent; use
39# a portion in the middle so that any ZFS label present on the real device
40# won't be present on the gnop device and vice versa.
41function create_gnop
42{
43	# Name of disk to use, with or without /dev/
44	typeset disk=$1
45	# Optional physical path to use
46	typeset physpath=$2
47	# size of disk in bytes
48	typeset -li disk_size
49	# disk size, rounded down to multiple of 16384
50	typeset -li disk_size_rounded
51	# size of the nop device in bytes
52	typeset -li nop_size
53	# offset of the beginning of the nop device in bytes
54	typeset -li nop_offset
55	typeset args
56
57	disk_size=`diskinfo $disk | cut -f 3`
58	# Round it down so the nop device will be 4k-aligned
59	disk_size_rounded=$(( ${disk_size} / 16384 * 16384 ))
60	nop_size=$(( ${disk_size_rounded} / 4 ))
61	nop_offset=${nop_size}
62	args="-s ${nop_size} -o ${nop_offset}"
63	if [ -n "$physpath" ]; then
64		args="$args -z $physpath"
65	fi
66
67	gnop create ${args} ${disk}
68}
69
70# Create multiple gnop devices
71function create_gnops
72{
73	typeset disk
74	for disk in $@; do
75		create_gnop "$disk" || return 1
76	done
77	return 0
78}
79
80# Destroy a gnop device.
81function destroy_gnop
82{
83	# Name of the underlying (non-gnop) device
84	typeset disk=$1
85
86	# Use "-f" so we can destroy a gnop with a consumer (like ZFS)
87	gnop destroy -f ${disk}.nop
88
89	# Wait for it to disappear
90	for i in `seq 5`; do
91		gnop status ${disk}.nop >/dev/null 2>/dev/null || break
92		sleep $i
93	done
94}
95
96# Destroy multiple gnop devices.  Attempt to destroy them all, ignoring errors
97function destroy_gnops
98{
99	typeset disk
100	for disk in $@; do
101		destroy_gnop "$disk"
102	done
103	return 0
104}
105