Import QEMU upstream snapshot d2e570c

Upstream: https://gitlab.com/qemu-project/qemu.git

Upstream-Commit: d2e570cc0f97b936902a5b1b86b73c0f5998b475

scripts/qemu-guest-agent/fsfreeze-hook

@@ -0,0 +1,76 @@
+#!/bin/sh
+
+# This script is executed when the guest agent receives fsfreeze-freeze and
+# fsfreeze-thaw commands, provided that the --fsfreeze-hook (-F) option of
+# qemu-ga is specified and the script is placed in /etc/qemu/fsfreeze-hook or in
+# the path specified together with -F. When the agent receives fsfreeze-freeze
+# requests, this script is called with "freeze" as its argument before the
+# filesystem is frozen. And for fsfreeze-thaw requests, it is called with "thaw"
+# as its argument after the filesystem is thawed.
+
+LOGFILE=/var/log/qga-fsfreeze-hook.log
+FSFREEZE_D=$(dirname -- "$0")/fsfreeze-hook.d
+
+# Check whether file $1 is a backup or rpm-generated file and should be ignored
+is_ignored_file() {
+    case "$1" in
+        *~ | *.bak | *.orig | *.rpmnew | *.rpmorig | *.rpmsave | *.sample | *.dpkg-old | *.dpkg-new | *.dpkg-tmp | *.dpkg-dist | *.dpkg-bak | *.dpkg-backup | *.dpkg-remove)
+            return 0 ;;
+    esac
+    return 1
+}
+
+USE_SYSLOG=0
+# if log file exists but is not writable, fallback to syslog
+[ -e "$LOGFILE" ] && [ ! -w "$LOGFILE" ] && USE_SYSLOG=1
+# try to update log file and fallback to syslog if it fails
+touch "$LOGFILE" >/dev/null 2>&1 || USE_SYSLOG=1
+
+# Ensure the log file is writable, fallback to syslog if not
+log_message() {
+    if [ "$USE_SYSLOG" -eq 0 ]; then
+        printf "%s: %s\n" "$(date)" "$1" >>"$LOGFILE"
+    else
+        logger -t qemu-ga-freeze-hook "$1"
+    fi
+}
+
+# Iterate executables in directory "fsfreeze-hook.d" with the specified args
+[ ! -d "$FSFREEZE_D" ] && exit 0
+
+for file in "$FSFREEZE_D"/* ; do
+    is_ignored_file "$file" && continue
+    [ -x "$file" ] || continue
+
+    log_message "Executing $file $*"
+    if [ "$USE_SYSLOG" -eq 0 ]; then
+        "$file" "$@" >>"$LOGFILE" 2>&1
+        STATUS=$?
+    else
+        # We want to pipe the output of $file through 'logger' and also
+        # capture its exit status. Since we are a POSIX script we can't
+        # use PIPESTATUS, so instead this is a trick borrowed from
+        # https://unix.stackexchange.com/questions/14270/get-exit-status-of-process-thats-piped-to-another/70675#70675
+        # which uses command-groups and redirection to get the exit status.
+        # This is equivalent to
+        #   "$file" "$@" 2>&1 | logger -t qemu-ga-freeze-hook
+        # plus setting the exit status of the pipe to the exit
+        # status of the first command rather than the last one.
+        { { { {
+                "$file" "$@" 2>&1 3>&- 4>&-
+                echo $? >&3
+            } | logger -t qemu-ga-freeze-hook >&4
+            } 3>&1
+          } | { read -r xs ; exit "$xs"; }
+        } 4>&1
+        STATUS=$?
+    fi
+
+    if [ "$STATUS" -ne 0 ]; then
+        log_message "Error: $file finished with status=$STATUS"
+    else
+        log_message "$file finished successfully"
+    fi
+done
+
+exit 0

scripts/qemu-guest-agent/fsfreeze-hook.d/mysql-flush.sh.sample

@@ -0,0 +1,56 @@
+#!/bin/sh
+
+# Flush MySQL tables to the disk before the filesystem is frozen.
+# At the same time, this keeps a read lock in order to avoid write accesses
+# from the other clients until the filesystem is thawed.
+
+MYSQL="/usr/bin/mysql"
+MYSQL_OPTS="-uroot" #"-prootpassword"
+FIFO=/var/run/mysql-flush.fifo
+
+# Check mysql is installed and the server running
+[ -x "$MYSQL" ] && "$MYSQL" $MYSQL_OPTS < /dev/null || exit 0
+
+flush_and_wait() {
+    printf "FLUSH TABLES WITH READ LOCK \\G\n"
+    trap 'printf "$(date): $0 is killed\n">&2' HUP INT QUIT ALRM TERM
+    read < $FIFO
+    printf "UNLOCK TABLES \\G\n"
+    rm -f $FIFO
+}
+
+case "$1" in
+    freeze)
+        mkfifo $FIFO || exit 1
+        flush_and_wait | "$MYSQL" $MYSQL_OPTS &
+        # wait until every block is flushed
+        while [ "$(echo 'SHOW STATUS LIKE "Key_blocks_not_flushed"' |\
+                 "$MYSQL" $MYSQL_OPTS | tail -1 | cut -f 2)" -gt 0 ]; do
+            sleep 1
+        done
+        # for InnoDB, wait until every log is flushed
+        INNODB_STATUS=$(mktemp /tmp/mysql-flush.XXXXXX)
+        [ $? -ne 0 ] && exit 2
+        trap "rm -f $INNODB_STATUS; exit 1" HUP INT QUIT ALRM TERM
+        while :; do
+            printf "SHOW ENGINE INNODB STATUS \\G" |\
+                "$MYSQL" $MYSQL_OPTS > $INNODB_STATUS
+            LOG_CURRENT=$(grep 'Log sequence number' $INNODB_STATUS |\
+                          tr -s ' ' | cut -d' ' -f4)
+            LOG_FLUSHED=$(grep 'Log flushed up to' $INNODB_STATUS |\
+                          tr -s ' ' | cut -d' ' -f5)
+            [ "$LOG_CURRENT" = "$LOG_FLUSHED" ] && break
+            sleep 1
+        done
+        rm -f $INNODB_STATUS
+        ;;
+
+    thaw)
+        [ ! -p $FIFO ] && exit 1
+        echo > $FIFO
+        ;;
+
+    *)
+        exit 1
+        ;;
+esac