From 59aa3bb5c84a8d2cfe8d27170bd826499710036e Mon Sep 17 00:00:00 2001
From: Nikolay Amiantov <ab@fmap.me>
Date: Mon, 8 Aug 2016 01:32:18 +0300
Subject: [PATCH 1/3] nixos stage-1: factor device waiting into a function

---
 nixos/modules/system/boot/stage-1-init.sh | 55 +++++++++++++----------
 1 file changed, 32 insertions(+), 23 deletions(-)

diff --git a/nixos/modules/system/boot/stage-1-init.sh b/nixos/modules/system/boot/stage-1-init.sh
index 7705dcb2d125e2..8e33705644d8dd 100644
--- a/nixos/modules/system/boot/stage-1-init.sh
+++ b/nixos/modules/system/boot/stage-1-init.sh
@@ -352,6 +352,33 @@ mountFS() {
 }
 
 
+# Function for waiting a device to appear.
+waitDevice() {
+    local device="$1"
+
+    # USB storage devices tend to appear with some delay.  It would be
+    # great if we had a way to synchronously wait for them, but
+    # alas...  So just wait for a few seconds for the device to
+    # appear.
+    if test ! -e $device; then
+        echo -n "waiting for device $device to appear..."
+        try=20
+        while [ $try -gt 0 ]; do
+            sleep 1
+            # also re-try lvm activation now that new block devices might have appeared
+            lvm vgchange -ay
+            # and tell udev to create nodes for the new LVs
+            udevadm trigger --action=add
+            if test -e $device; then break; fi
+            echo -n "."
+            try=$((try - 1))
+        done
+        echo
+        [ $try -ne 0 ]
+    fi
+}
+
+
 # Try to find and mount the root device.
 mkdir -p $targetRoot
 
@@ -384,29 +411,11 @@ while read -u 3 mountPoint; do
             ;;
     esac
 
-    # USB storage devices tend to appear with some delay.  It would be
-    # great if we had a way to synchronously wait for them, but
-    # alas...  So just wait for a few seconds for the device to
-    # appear.  If it doesn't appear, try to mount it anyway (and
-    # probably fail).  This is a fallback for non-device "devices"
-    # that we don't properly recognise.
-    if test -z "$pseudoDevice" -a ! -e $device; then
-        echo -n "waiting for device $device to appear..."
-        try=20
-        while [ $try -gt 0 ]; do
-            sleep 1
-            # also re-try lvm activation now that new block devices might have appeared
-            lvm vgchange -ay
-            # and tell udev to create nodes for the new LVs
-            udevadm trigger --action=add
-            if test -e $device; then break; fi
-            echo -n "."
-            try=$((try - 1))
-        done
-        echo
-        if [ $try -eq 0 ]; then
-          echo "Timed out waiting for device $device, trying to mount anyway."
-        fi
+    if test -z "$pseudoDevice" && ! waitDevice "$device"; then
+        # If it doesn't appear, try to mount it anyway (and
+        # probably fail).  This is a fallback for non-device "devices"
+        # that we don't properly recognise.
+        echo "Timed out waiting for device $device, trying to mount anyway."
     fi
 
     # Wait once more for the udev queue to empty, just in case it's

From 3ae468e8355494dda2e9c28b5d62d3c03bf4ce98 Mon Sep 17 00:00:00 2001
From: Nikolay Amiantov <ab@fmap.me>
Date: Mon, 8 Aug 2016 01:34:23 +0300
Subject: [PATCH 2/3] nixos stage-1: move resumption below helper functions'
 definitions

---
 nixos/modules/system/boot/stage-1-init.sh | 66 +++++++++++------------
 1 file changed, 33 insertions(+), 33 deletions(-)

diff --git a/nixos/modules/system/boot/stage-1-init.sh b/nixos/modules/system/boot/stage-1-init.sh
index 8e33705644d8dd..fc50481e0bc8b9 100644
--- a/nixos/modules/system/boot/stage-1-init.sh
+++ b/nixos/modules/system/boot/stage-1-init.sh
@@ -189,39 +189,6 @@ if test -n "$debug1devices"; then fail; fi
 @postDeviceCommands@
 
 
-# Try to resume - all modules are loaded now, and devices exist
-if test -e /sys/power/tuxonice/resume; then
-    if test -n "$(cat /sys/power/tuxonice/resume)"; then
-        echo 0 > /sys/power/tuxonice/user_interface/enabled
-        echo 1 > /sys/power/tuxonice/do_resume || echo "failed to resume..."
-    fi
-fi
-
-if test -e /sys/power/resume -a -e /sys/power/disk; then
-    if test -n "@resumeDevice@"; then
-        resumeDev="@resumeDevice@"
-        resumeInfo="$(udevadm info -q property "$resumeDev" )"
-    else
-        for sd in @resumeDevices@; do
-            # Try to detect resume device. According to Ubuntu bug:
-            # https://bugs.launchpad.net/ubuntu/+source/pm-utils/+bug/923326/comments/1
-            # when there are multiple swap devices, we can't know where the hibernate
-            # image will reside. We can check all of them for swsuspend blkid.
-            resumeInfo="$(test -e "$sd" && udevadm info -q property "$sd")"
-            if [ "$(echo "$resumeInfo" | sed -n 's/^ID_FS_TYPE=//p')" = "swsuspend" ]; then
-                resumeDev="$sd"
-                break
-            fi
-        done
-    fi
-    if test -e "$resumeDev"; then
-        resumeMajor="$(echo "$resumeInfo" | sed -n 's/^MAJOR=//p')"
-        resumeMinor="$(echo "$resumeInfo" | sed -n 's/^MINOR=//p')"
-        echo "$resumeMajor:$resumeMinor" > /sys/power/resume 2> /dev/null || echo "failed to resume..."
-    fi
-fi
-
-
 # Return true if the machine is on AC power, or if we can't determine
 # whether it's on AC power.
 onACPower() {
@@ -379,6 +346,39 @@ waitDevice() {
 }
 
 
+# Try to resume - all modules are loaded now, and devices exist
+if test -e /sys/power/tuxonice/resume; then
+    if test -n "$(cat /sys/power/tuxonice/resume)"; then
+        echo 0 > /sys/power/tuxonice/user_interface/enabled
+        echo 1 > /sys/power/tuxonice/do_resume || echo "failed to resume..."
+    fi
+fi
+
+if test -e /sys/power/resume -a -e /sys/power/disk; then
+    if test -n "@resumeDevice@"; then
+        resumeDev="@resumeDevice@"
+        resumeInfo="$(udevadm info -q property "$resumeDev" )"
+    else
+        for sd in @resumeDevices@; do
+            # Try to detect resume device. According to Ubuntu bug:
+            # https://bugs.launchpad.net/ubuntu/+source/pm-utils/+bug/923326/comments/1
+            # when there are multiple swap devices, we can't know where the hibernate
+            # image will reside. We can check all of them for swsuspend blkid.
+            resumeInfo="$(test -e "$sd" && udevadm info -q property "$sd")"
+            if [ "$(echo "$resumeInfo" | sed -n 's/^ID_FS_TYPE=//p')" = "swsuspend" ]; then
+                resumeDev="$sd"
+                break
+            fi
+        done
+    fi
+    if test -e "$resumeDev"; then
+        resumeMajor="$(echo "$resumeInfo" | sed -n 's/^MAJOR=//p')"
+        resumeMinor="$(echo "$resumeInfo" | sed -n 's/^MINOR=//p')"
+        echo "$resumeMajor:$resumeMinor" > /sys/power/resume 2> /dev/null || echo "failed to resume..."
+    fi
+fi
+
+
 # Try to find and mount the root device.
 mkdir -p $targetRoot
 

From 986a40421a94528c55531719fb382160292c7e16 Mon Sep 17 00:00:00 2001
From: Nikolay Amiantov <ab@fmap.me>
Date: Mon, 8 Aug 2016 01:35:43 +0300
Subject: [PATCH 3/3] nixos stage-1: wait for devices during resumption attempt

Also a microimprovement -- use `test -n` instead of `test -e`
since we have already checked that the file exists.
---
 nixos/modules/system/boot/stage-1-init.sh | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/nixos/modules/system/boot/stage-1-init.sh b/nixos/modules/system/boot/stage-1-init.sh
index fc50481e0bc8b9..ef04629d735f69 100644
--- a/nixos/modules/system/boot/stage-1-init.sh
+++ b/nixos/modules/system/boot/stage-1-init.sh
@@ -346,7 +346,7 @@ waitDevice() {
 }
 
 
-# Try to resume - all modules are loaded now, and devices exist
+# Try to resume - all modules are loaded now.
 if test -e /sys/power/tuxonice/resume; then
     if test -n "$(cat /sys/power/tuxonice/resume)"; then
         echo 0 > /sys/power/tuxonice/user_interface/enabled
@@ -355,7 +355,7 @@ if test -e /sys/power/tuxonice/resume; then
 fi
 
 if test -e /sys/power/resume -a -e /sys/power/disk; then
-    if test -n "@resumeDevice@"; then
+    if test -n "@resumeDevice@" && waitDevice "@resumeDevice@"; then
         resumeDev="@resumeDevice@"
         resumeInfo="$(udevadm info -q property "$resumeDev" )"
     else
@@ -364,14 +364,16 @@ if test -e /sys/power/resume -a -e /sys/power/disk; then
             # https://bugs.launchpad.net/ubuntu/+source/pm-utils/+bug/923326/comments/1
             # when there are multiple swap devices, we can't know where the hibernate
             # image will reside. We can check all of them for swsuspend blkid.
-            resumeInfo="$(test -e "$sd" && udevadm info -q property "$sd")"
-            if [ "$(echo "$resumeInfo" | sed -n 's/^ID_FS_TYPE=//p')" = "swsuspend" ]; then
-                resumeDev="$sd"
-                break
+            if waitDevice "$sd"; then
+                resumeInfo="$(udevadm info -q property "$sd")"
+                if [ "$(echo "$resumeInfo" | sed -n 's/^ID_FS_TYPE=//p')" = "swsuspend" ]; then
+                    resumeDev="$sd"
+                    break
+                fi
             fi
         done
     fi
-    if test -e "$resumeDev"; then
+    if test -n "$resumeDev"; then
         resumeMajor="$(echo "$resumeInfo" | sed -n 's/^MAJOR=//p')"
         resumeMinor="$(echo "$resumeInfo" | sed -n 's/^MINOR=//p')"
         echo "$resumeMajor:$resumeMinor" > /sys/power/resume 2> /dev/null || echo "failed to resume..."