path: root/qemu-options.hx
diff options
authorDaniel P. Berrange <berrange@redhat.com>2016-01-11 12:44:41 +0000
committerPaolo Bonzini <pbonzini@redhat.com>2016-01-15 18:58:02 +0100
commitd0d7708ba29cbcc343364a46bff981e0ff88366f (patch)
treec8cdee194dc2a941021082b68dfd5cbeff9752db /qemu-options.hx
parentf1c17521e79df863a5771d96974fab0d07f02be0 (diff)
qemu-char: add logfile facility to all chardev backends
Typically a UNIX guest OS will log boot messages to a serial port in addition to any graphical console. An admin user may also wish to use the serial port for an interactive console. A virtualization management system may wish to collect system boot messages by logging the serial port, but also wish to allow admins interactive access. Currently providing such a feature forces the mgmt app to either provide 2 separate serial ports, one for logging boot messages and one for interactive console login, or to proxy all output via a separate service that can multiplex the two needs onto one serial port. While both are valid approaches, they each have their own downsides. The former causes confusion and extra setup work for VM admins creating disk images. The latter places an extra burden to re-implement much of the QEMU chardev backends logic in libvirt or even higher level mgmt apps and adds extra hops in the data transfer path. A simpler approach that is satisfactory for many use cases is to allow the QEMU chardev backends to have a "logfile" property associated with them. $QEMU -chardev socket,host=localhost,port=9000,\ server=on,nowait,id-charserial0,\ logfile=/var/log/libvirt/qemu/test-serial0.log -device isa-serial,chardev=charserial0,id=serial0 This patch introduces a 'ChardevCommon' struct which is setup as a base for all the ChardevBackend types. Ideally this would be registered directly as a base against ChardevBackend, rather than each type, but the QAPI generator doesn't allow that since the ChardevBackend is a non-discriminated union. The ChardevCommon struct provides the optional 'logfile' parameter, as well as 'logappend' which controls whether QEMU truncates or appends (default truncate). Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1452516281-27519-1-git-send-email-berrange@redhat.com> [Call qemu_chr_parse_common if cd->parse is NULL. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'qemu-options.hx')
1 files changed, 28 insertions, 20 deletions
diff --git a/qemu-options.hx b/qemu-options.hx
index 215d00ddd3..b4763ba226 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -2089,40 +2089,43 @@ The general form of a character device option is:
DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
- "-chardev null,id=id[,mux=on|off]\n"
+ "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
"-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
- " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off] (tcp)\n"
- "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off] (unix)\n"
+ " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n"
+ " [,logfile=PATH][,logappend=on|off] (tcp)\n"
+ "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n"
+ " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n"
"-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
" [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
- "-chardev msmouse,id=id[,mux=on|off]\n"
+ " [,logfile=PATH][,logappend=on|off]\n"
+ "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
"-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
- " [,mux=on|off]\n"
- "-chardev ringbuf,id=id[,size=size]\n"
- "-chardev file,id=id,path=path[,mux=on|off]\n"
- "-chardev pipe,id=id,path=path[,mux=on|off]\n"
+ " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
+ "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n"
+ "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
+ "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
#ifdef _WIN32
- "-chardev console,id=id[,mux=on|off]\n"
- "-chardev serial,id=id,path=path[,mux=on|off]\n"
+ "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
+ "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
- "-chardev pty,id=id[,mux=on|off]\n"
- "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n"
+ "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
+ "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n"
- "-chardev braille,id=id[,mux=on|off]\n"
+ "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
|| defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
- "-chardev serial,id=id,path=path[,mux=on|off]\n"
- "-chardev tty,id=id,path=path[,mux=on|off]\n"
+ "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
+ "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
- "-chardev parallel,id=id,path=path[,mux=on|off]\n"
- "-chardev parport,id=id,path=path[,mux=on|off]\n"
+ "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
+ "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
#if defined(CONFIG_SPICE)
- "-chardev spicevmc,id=id,name=name[,debug=debug]\n"
- "-chardev spiceport,id=id,name=name[,debug=debug]\n"
+ "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
+ "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
@@ -2158,7 +2161,12 @@ A character device may be used in multiplexing mode by multiple front-ends.
The key sequence of @key{Control-a} and @key{c} will rotate the input focus
between attached front-ends. Specify @option{mux=on} to enable this mode.
-Options to each backend are described below.
+Every backend supports the @option{logfile} option, which supplies the path
+to a file to record all data transmitted via the backend. The @option{logappend}
+option controls whether the log file will be truncated or appended to when
+Further options to each backend are described below.
@item -chardev null ,id=@var{id}
A void device. This device will not emit any data, and will drop any data it