Re: [Qemu-devel] [PATCH] allow bootdevice change from the monitor

[Aurelien Jarno]

On Wed, Mar 26, 2008 at 02:12:25PM +0100, Gildas wrote:
> This patch allows changing the boot device from within the monitor.

I have just updated BOCHS BIOS from upstream CVS. The new version allows
to select the boot device via a menu after the POST. I am therefore not
sure anymore that your patch is still useful. What do you think?

> Signed-off-by: Gildas Le Nadan <address@hidden>
> 
> diff -Nur a/hw/pc.c b/hw/pc.c
> --- a/hw/pc.c   2008-03-18 07:53:05.000000000 +0100
> +++ b/hw/pc.c   2008-03-26 13:18:16.000000000 +0100
> @@ -180,6 +180,33 @@
>      return 0;
>  }
> 
> +/* copy/pasted from cmos_init, should be made a general function
> + and used there as well */
> +int pc_set_bootdevice(const char *boot_device)
> +{
> +#define PC_MAX_BOOT_DEVICES 3
> +    RTCState *s = rtc_state;
> +    int nbds, bds[3] = { 0, };
> +    int i;
> +
> +    nbds = strlen(boot_device);
> +    if (nbds > PC_MAX_BOOT_DEVICES) {
> +        fprintf(stderr, "Too many boot devices for PC\n");
> +        return(1);
> +    }
> +    for (i = 0; i < nbds; i++) {
> +        bds[i] = boot_device2nibble(boot_device[i]);
> +        if (bds[i] == 0) {
> +            fprintf(stderr, "Invalid boot device for PC: '%c'\n",
> +                    boot_device[i]);
> +            return(1);
> +        }
> +    }
> +    rtc_set_memory(s, 0x3d, (bds[1] << 4) | bds[0]);
> +    rtc_set_memory(s, 0x38, (bds[2] << 4));
> +    return(0);
> +}
> +
>  /* hd_table must contain 4 block drivers */
>  static void cmos_init(int ram_size, const char *boot_device,
> BlockDriverState **hd_table)
>  {
> @@ -717,6 +744,8 @@
>      BlockDriverState *hd[MAX_IDE_BUS * MAX_IDE_DEVS];
>      BlockDriverState *fd[MAX_FD];
> 
> +    set_bootdevice_fct = pc_set_bootdevice;
> +
>      linux_boot = (kernel_filename != NULL);
> 
>      /* init CPUs */
> diff -Nur a/monitor.c b/monitor.c
> --- a/monitor.c 2008-02-10 17:33:13.000000000 +0100
> +++ b/monitor.c 2008-03-26 13:17:56.000000000 +0100
> @@ -993,6 +993,21 @@
>                  suffix, addr, size * 2, val);
>  }
> 
> +static void do_bootdevice_set(const char *bootdevice)
> +{
> +    int res;
> +
> +    if (set_bootdevice_fct != NULL)  {
> +        res = set_bootdevice_fct(bootdevice);
> +        if (res == 0)
> +            term_printf("boot device list now set to %s\n", bootdevice);
> +        else
> +            term_printf("setting boot device list failed with error
> %i\n", res);
> +    } else {
> +        term_printf("no function defined to set boot device list for
> this architecture\n");
> +    }
> +}
> +
>  static void do_system_reset(void)
>  {
>      qemu_system_reset_request();
> @@ -1328,6 +1343,8 @@
>         "capture index", "stop capture" },
>      { "memsave", "lis", do_memory_save,
>        "addr size file", "save to disk virtual memory dump starting at
> 'addr' of size 'size'", },
> +    { "boot_set", "s", do_bootdevice_set,
> +      "bootdevice", "define new values for the boot device list" },
>      { NULL, NULL, },
>  };
> 
> diff -Nur a/sysemu.h b/sysemu.h
> --- a/sysemu.h  2008-03-18 07:53:05.000000000 +0100
> +++ b/sysemu.h  2008-03-26 13:12:20.000000000 +0100
> @@ -9,6 +9,11 @@
>  extern int vm_running;
>  extern const char *qemu_name;
> 
> +/* handler to set the boot_device for a specific type of QEMUMachine */
> +/* return 0 if success */
> +typedef int QEMUMachineSetBootFunc(const char *boot_device);
> +QEMUMachineSetBootFunc *set_bootdevice_fct;
> +
>  typedef struct vm_change_state_entry VMChangeStateEntry;
>  typedef void VMChangeStateHandler(void *opaque, int running);
>  typedef void VMStopHandler(void *opaque, int reason);
> 
> 
> 

-- 
  .''`.  Aurelien Jarno             | GPG: 1024D/F1BCDB73
 : :' :  Debian developer           | Electrical Engineer
 `. `'   address@hidden         | address@hidden
   `-    people.debian.org/~aurel32 | www.aurel32.net