os-posix: Allow 'chroot' via '-run-with' and deprecate the old '-chroot' option

We recently introduced "-run-with" for options that influence the
runtime behavior of QEMU. This option has the big advantage that it
can group related options (so that it is easier for the users to spot
them) and that the options become introspectable via QMP this way.
So let's start moving more switches into this option group, starting
with "-chroot" now.

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Message-Id: <20230703074447.17044-1-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
This commit is contained in:
Thomas Huth 2023-07-03 09:44:47 +02:00
parent bc55e2eaa6
commit 9ffcbe2a60
4 changed files with 52 additions and 27 deletions

View File

@ -116,6 +116,11 @@ Use "whpx" (on Windows) or "hvf" (on macOS) instead.
Use ``-run-with async-teardown=on`` instead.
``-chroot`` (since 8.1)
'''''''''''''''''''''''
Use ``-run-with chroot=dir`` instead.
``-singlestep`` (since 8.1)
'''''''''''''''''''''''''''

View File

@ -38,6 +38,7 @@
#include "qemu/cutils.h"
#include "qemu/config-file.h"
#include "qemu/option.h"
#include "qemu/module.h"
#ifdef CONFIG_LINUX
#include <sys/prctl.h>
@ -148,6 +149,7 @@ int os_parse_cmd_args(int index, const char *optarg)
}
break;
case QEMU_OPTION_chroot:
warn_report("option is deprecated, use '-run-with chroot=...' instead");
chroot_dir = optarg;
break;
case QEMU_OPTION_daemonize:
@ -158,18 +160,25 @@ int os_parse_cmd_args(int index, const char *optarg)
case QEMU_OPTION_asyncteardown:
init_async_teardown();
break;
#endif
case QEMU_OPTION_run_with: {
const char *str;
QemuOpts *opts = qemu_opts_parse_noisily(qemu_find_opts("run-with"),
optarg, false);
if (!opts) {
exit(1);
}
#if defined(CONFIG_LINUX)
if (qemu_opt_get_bool(opts, "async-teardown", false)) {
init_async_teardown();
}
#endif
str = qemu_opt_get(opts, "chroot");
if (str) {
chroot_dir = str;
}
break;
}
#endif
default:
return -1;
}
@ -348,3 +357,27 @@ int os_mlock(void)
return -ENOSYS;
#endif
}
static QemuOptsList qemu_run_with_opts = {
.name = "run-with",
.head = QTAILQ_HEAD_INITIALIZER(qemu_run_with_opts.head),
.desc = {
#if defined(CONFIG_LINUX)
{
.name = "async-teardown",
.type = QEMU_OPT_BOOL,
},
#endif
{
.name = "chroot",
.type = QEMU_OPT_STRING,
},
{ /* end of list */ }
},
};
static void register_runwith(void)
{
qemu_add_opts(&qemu_run_with_opts);
}
opts_init(register_runwith);

View File

@ -4677,11 +4677,12 @@ ERST
#ifndef _WIN32
DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
"-chroot dir chroot to dir just before starting the VM\n",
"-chroot dir chroot to dir just before starting the VM (deprecated)\n",
QEMU_ARCH_ALL)
#endif
SRST
``-chroot dir``
Deprecated, use '-run-with chroot=...' instead.
Immediately before starting guest execution, chroot to the specified
directory. Especially useful in combination with -runas.
ERST
@ -4868,13 +4869,16 @@ SRST
This option is deprecated and should no longer be used. The new option
``-run-with async-teardown=on`` is a replacement.
ERST
#endif
#ifdef CONFIG_POSIX
DEF("run-with", HAS_ARG, QEMU_OPTION_run_with,
"-run-with async-teardown[=on|off]\n"
" misc QEMU process lifecycle options\n"
" async-teardown=on enables asynchronous teardown\n",
"-run-with [async-teardown=on|off][,chroot=dir]\n"
" Set miscellaneous QEMU process lifecycle options:\n"
" async-teardown=on enables asynchronous teardown (Linux only)\n"
" chroot=dir chroot to dir just before starting the VM\n",
QEMU_ARCH_ALL)
SRST
``-run-with``
``-run-with [async-teardown=on|off][,chroot=dir]``
Set QEMU process lifecycle options.
``async-teardown=on`` enables asynchronous teardown. A new process called
@ -4887,6 +4891,10 @@ SRST
performed correctly. This only works if the cleanup process is not
forcefully killed with SIGKILL before the main QEMU process has
terminated completely.
``chroot=dir`` can be used for doing a chroot to the specified directory
immediately before starting the guest execution. This is especially useful
in combination with -runas.
ERST
#endif

View File

@ -12,9 +12,6 @@
*/
#include "qemu/osdep.h"
#include "qemu/config-file.h"
#include "qemu/option.h"
#include "qemu/module.h"
#include <dirent.h>
#include <sys/prctl.h>
#include <sched.h>
@ -147,21 +144,3 @@ void init_async_teardown(void)
clone(async_teardown_fn, new_stack_for_clone(), CLONE_VM, NULL);
sigprocmask(SIG_SETMASK, &old_signals, NULL);
}
static QemuOptsList qemu_run_with_opts = {
.name = "run-with",
.head = QTAILQ_HEAD_INITIALIZER(qemu_run_with_opts.head),
.desc = {
{
.name = "async-teardown",
.type = QEMU_OPT_BOOL,
},
{ /* end of list */ }
},
};
static void register_teardown(void)
{
qemu_add_opts(&qemu_run_with_opts);
}
opts_init(register_teardown);