Re: [PATCH] vl, pc: turn -no-fd-bootchk into a machine property

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 20/2/24 16:53, Paolo Bonzini wrote:
> Add a fd-bootchk property to PC machine types, so that -no-fd-bootchk
> returns an error if the machine does not support booting from floppies
> and checking for boot signatures therein.
> 
> Suggested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>   include/hw/i386/pc.h |  2 +-
>   hw/i386/pc.c         | 30 +++++++++++++++++++++++++-----
>   system/globals.c     |  1 -
>   system/vl.c          |  2 +-
>   qemu-options.hx      |  2 +-
>   5 files changed, 28 insertions(+), 9 deletions(-)
> 
> diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
> index 02a0deedd3c..e5382a02e7a 100644
> --- a/include/hw/i386/pc.h
> +++ b/include/hw/i386/pc.h
> @@ -50,6 +50,7 @@ typedef struct PCMachineState {
>       bool hpet_enabled;
>       bool i8042_enabled;
>       bool default_bus_bypass_iommu;
> +    bool fd_bootchk;
>       uint64_t max_fw_size;
>   
>       /* ACPI Memory hotplug IO base address */
> @@ -147,7 +148,6 @@ OBJECT_DECLARE_TYPE(PCMachineState, PCMachineClass, PC_MACHINE)
>   GSIState *pc_gsi_create(qemu_irq **irqs, bool pci_enabled);
>   
>   /* pc.c */
> -extern int fd_bootchk;
>   
>   void pc_acpi_smi_interrupt(void *opaque, int irq, int level);
>   
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index 28194014f82..31f4bb25a3e 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -399,8 +399,8 @@ static int boot_device2nibble(char boot_device)
>       return 0;
>   }
>   
> -static void set_boot_dev(MC146818RtcState *s, const char *boot_device,
> -                         Error **errp)
> +static void set_boot_dev(PCMachineState *pcms, MC146818RtcState *s,
> +                         const char *boot_device, Error **errp)
>   {
>   #define PC_MAX_BOOT_DEVICES 3
>       int nbds, bds[3] = { 0, };
> @@ -420,12 +420,14 @@ static void set_boot_dev(MC146818RtcState *s, const char *boot_device,
>           }
>       }
>       mc146818rtc_set_cmos_data(s, 0x3d, (bds[1] << 4) | bds[0]);
> -    mc146818rtc_set_cmos_data(s, 0x38, (bds[2] << 4) | (fd_bootchk ? 0x0 : 0x1));
> +    mc146818rtc_set_cmos_data(s, 0x38, (bds[2] << 4) | !pcms->fd_bootchk);
>   }
>   
>   static void pc_boot_set(void *opaque, const char *boot_device, Error **errp)
>   {
> -    set_boot_dev(opaque, boot_device, errp);
> +    PCMachineState *pcms = PC_MACHINE(current_machine);
> +
> +    set_boot_dev(pcms, opaque, boot_device, errp);
>   }
>   
>   static void pc_cmos_init_floppy(MC146818RtcState *rtc_state, ISADevice *floppy)
> @@ -617,6 +619,9 @@ void pc_cmos_init(PCMachineState *pcms,
>       mc146818rtc_set_cmos_data(s, 0x5c, val >> 8);
>       mc146818rtc_set_cmos_data(s, 0x5d, val >> 16);
>   
> +    object_property_add_bool(obj, "fd-bootchk", pc_machine_get_fd_bootchk,
> +                             pc_machine_set_fd_bootchk);
> +
>       object_property_add_link(OBJECT(pcms), "rtc_state",
>                                TYPE_ISA_DEVICE,
>                                (Object **)&x86ms->rtc,
> @@ -625,7 +630,7 @@ void pc_cmos_init(PCMachineState *pcms,
>       object_property_set_link(OBJECT(pcms), "rtc_state", OBJECT(s),
>                                &error_abort);
>   
> -    set_boot_dev(s, MACHINE(pcms)->boot_config.order, &error_fatal);
> +    set_boot_dev(pcms, s, MACHINE(pcms)->boot_config.order, &error_fatal);
>   
>       val = 0;
>       val |= 0x02; /* FPU is there */
> @@ -1559,6 +1564,20 @@ static void pc_machine_set_vmport(Object *obj, Visitor *v, const char *name,
>       visit_type_OnOffAuto(v, name, &pcms->vmport, errp);
>   }
>   
> +static bool pc_machine_get_fd_bootchk(Object *obj, Error **errp)
> +{
> +    PCMachineState *pcms = PC_MACHINE(obj);
> +
> +    return pcms->fd_bootchk;
> +}
> +
> +static void pc_machine_set_fd_bootchk(Object *obj, bool value, Error **errp)
> +{
> +    PCMachineState *pcms = PC_MACHINE(obj);
> +
> +    pcms->fd_bootchk = value;
> +}
> +
>   static bool pc_machine_get_smbus(Object *obj, Error **errp)
>   {
>       PCMachineState *pcms = PC_MACHINE(obj);
> @@ -1747,6 +1766,7 @@ static void pc_machine_initfn(Object *obj)
>   #ifdef CONFIG_HPET
>       pcms->hpet_enabled = true;
>   #endif
> +    pcms->fd_bootchk = true;
>       pcms->default_bus_bypass_iommu = false;
>   
>       pc_system_flash_create(pcms);
> diff --git a/system/globals.c b/system/globals.c
> index b6d4e72530e..5d0046ba105 100644
> --- a/system/globals.c
> +++ b/system/globals.c
> @@ -41,7 +41,6 @@ int vga_interface_type = VGA_NONE;
>   bool vga_interface_created;
>   Chardev *parallel_hds[MAX_PARALLEL_PORTS];
>   int win2k_install_hack;
> -int fd_bootchk = 1;
>   int graphic_rotate;
>   QEMUOptionRom option_rom[MAX_OPTION_ROMS];
>   int nb_option_roms;
> diff --git a/system/vl.c b/system/vl.c
> index a82555ae155..4627004304b 100644
> --- a/system/vl.c
> +++ b/system/vl.c
> @@ -2927,7 +2927,7 @@ void qemu_init(int argc, char **argv)
>                             optarg, FD_OPTS);
>                   break;
>               case QEMU_OPTION_no_fd_bootchk:
> -                fd_bootchk = 0;
> +                qdict_put_str(machine_opts_dict, "fd-bootchk", "off");
>                   break;
>               case QEMU_OPTION_netdev:
>                   default_net = 0;
> diff --git a/qemu-options.hx b/qemu-options.hx
> index 8547254dbf9..a9e0107b4f0 100644
> --- a/qemu-options.hx
> +++ b/qemu-options.hx
> @@ -2650,7 +2650,7 @@ DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
>   SRST
>   ``-no-fd-bootchk``
>       Disable boot signature checking for floppy disks in BIOS. May be
> -    needed to boot from old floppy disks.
> +    needed to boot from old floppy disks.  Synonym of ``-m fd-bootchk=off``.

Thank you!

Shouldn't we deprecate -no-fd-bootchk in favor of -m fd-bootchk=off?

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

>   ERST
>   
>   DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,