允许WordPress对Docker挂载的文件夹进行写入访问

我有一个Docker设置，与Ubuntu、Nginx、PHP-FPM和MySQL配合良好。

WordPress可以写到uploads文件夹，我可以在线编辑模板，但当我试图升级WordPress或插件时，它失败了。

拆开更新的包装...

无法创建目录: wordpress

我对整个WordPress文件夹进行了 chmod 777 ，所以我不确定这是否与Docker或WordPress有关。我也检查了各种日志，但我发现唯一相关的一行是这样的。

192.168.59.3 - - [01/Oct/2014:14:16:58 +0000] "POST /wp-admin/update-core.php?action=do-core-upgrade HTTP/1.1" 200 5576 "/wp-admin/update-core.php" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/37.0.2062.124 Safari/537.36"

下面是我创建Docker环境的过程。

brew install docker boot2docker
boot2docker init
# Allow VM access to our space
curl http://static.dockerfiles.io/boot2docker-v1.2.0-virtualbox-guest-additions-v4.3.14.iso > ~/.boot2docker/boot2docker.iso
VBoxManage sharedfolder add boot2docker-vm -name home -hostpath /Users
boot2docker up
下面是我启动容器的方法。
docker run -p 80:80 --name wp -d -v ~/wordpress:/mnt/www:rw wp
下面是Nginx的配置。
server {
    listen   80; ## listen for ipv4; this line is default and implied
    listen   [::]:80 default ipv6only=on; ## listen for ipv6
    root /mnt/www;
    index index.php index.html index.htm;
    # Make site accessible from http://localhost/
    server_name localhost;
    location / {
        # First attempt to serve request as file, then
# as directory, then fall back to index.html
        try_files $uri $uri/ /index.php?q=$uri&$args;
    #error_page 404 /404.html;
# redirect server error pages to the static page /50x.html
    error_page 500 502 503 504 /50x.html;
    location = /50x.html {
        root /usr/share/nginx/www;
    # pass the PHP scripts to FastCGI server
    location ~ \.php$ {
    try_files $uri =404;
        fastcgi_split_path_info ^(.+\.php)(/.+)$;
        # NOTE: You should have "cgi.fix_pathinfo = 0;" in php.ini
        fastcgi_pass unix:/var/run/php5-fpm.sock;
        fastcgi_index index.php;
        include fastcgi_params;