Re: [Qemu-devel] [PATCH 5/6] hw/nvram/fw_cfg: Add HMP 'info fw_cfg' command

["Michael S. Tsirkin" <mst@redhat.com>]

On Fri, Dec 07, 2018 at 06:03:59PM +0100, Philippe Mathieu-Daudé wrote:
> $ qemu-system-x86_64 -S -monitor stdio
> (qemu) info fw_cfg
>         Type    Perm    Size    Specific   Order   Info

Can we do better than "Info"?

>    signature      RO       4                       QEMU
>           id      RO       4                       0x00000003
>         uuid      RO      16                       00000000-0000-0000-0000-000000000000
>     ram_size      RO       8                       0x0000000008000000
>    nographic      RO       2                       0x0000
>      nb_cpus      RO       2                       0x0001
>         numa      RO      16
>    boot_menu      RO       2                       0x0000
>     max_cpus      RO       2                       0x0001
>     file_dir      RO    2052
>  file (id 1)      RO      36                 160   etc/acpi/rsdp
>  file (id 2)      RO  131072                 130   etc/acpi/tables
>  file (id 3)      RO       4                  15   etc/boot-fail-wait
>  file (id 4)      RO      20                  40   etc/e820
>  file (id 5)      RO      31                  30   etc/smbios/smbios-anchor
>  file (id 6)      RO     320                  20   etc/smbios/smbios-tables
>  file (id 7)      RO       6                  90   etc/system-states
>  file (id 8)      RO    4096                 140   etc/table-loader
> file (id 10)      RO    9216                  55   genroms/kvmvapic.bin
>         uuid      RO       4  (arch spec)          01000000-0000-0000-0000-000000000000
>     ram_size      RO     324  (arch spec)
>    nographic      RO     121  (arch spec)

Weird. Your code has arch_spec.

> (qemu)
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>


Looks helpful but generally IMHO whatever is exposed through hmp
should be in the qmp as well.


> ---
>  hmp-commands-info.hx      |  14 +++++
>  hw/nvram/fw_cfg.c         | 115 ++++++++++++++++++++++++++++++++++++++
>  include/hw/nvram/fw_cfg.h |   2 +
>  3 files changed, 131 insertions(+)
> 
> diff --git a/hmp-commands-info.hx b/hmp-commands-info.hx
> index cbee8b944d..9e86dceeb4 100644
> --- a/hmp-commands-info.hx
> +++ b/hmp-commands-info.hx
> @@ -916,6 +916,20 @@ STEXI
>  @item info sev
>  @findex info sev
>  Show SEV information.
> +ETEXI
> +
> +    {
> +        .name       = "fw_cfg",
> +        .args_type  = "",
> +        .params     = "",
> +        .help       = "Display the table of the fw_cfg entries registered",

I think the help line should be a bit more verbose.
Mention it's a paravirtualized interface, and why
would one want to display it (debugging guest firmware?).


> +        .cmd        = hmp_info_fw_cfg,
> +    },
> +
> +STEXI
> +@item info fw_cfg
> +@findex info fw_cfg
> +Show roms.
>  ETEXI
>  
>  STEXI
> diff --git a/hw/nvram/fw_cfg.c b/hw/nvram/fw_cfg.c
> index 582653f07e..50525ec1dd 100644
> --- a/hw/nvram/fw_cfg.c
> +++ b/hw/nvram/fw_cfg.c
> @@ -36,6 +36,7 @@
>  #include "qemu/config-file.h"
>  #include "qemu/cutils.h"
>  #include "qapi/error.h"
> +#include "monitor/monitor.h"
>  
>  #define FW_CFG_FILE_SLOTS_DFLT 0x20
>  
> @@ -1164,3 +1165,117 @@ static void fw_cfg_register_types(void)
>  }
>  
>  type_init(fw_cfg_register_types)
> +
> +static const char *fw_cfg_wellknown_entries[0x20] = {
> +    [FW_CFG_SIGNATURE] = "signature",
> +    [FW_CFG_ID] = "id",
> +    [FW_CFG_UUID] = "uuid",
> +    [FW_CFG_RAM_SIZE] = "ram_size",
> +    [FW_CFG_NOGRAPHIC] = "nographic",
> +    [FW_CFG_NB_CPUS] = "nb_cpus",
> +    [FW_CFG_MACHINE_ID] = "machine_id",
> +    [FW_CFG_KERNEL_ADDR] = "kernel_addr",
> +    [FW_CFG_KERNEL_SIZE] = "kernel_size",
> +    [FW_CFG_KERNEL_CMDLINE] = "kernel_cmdline",
> +    [FW_CFG_INITRD_ADDR] = "initrd_addr",
> +    [FW_CFG_INITRD_SIZE] = "initdr_size",
> +    [FW_CFG_BOOT_DEVICE] = "boot_device",
> +    [FW_CFG_NUMA] = "numa",
> +    [FW_CFG_BOOT_MENU] = "boot_menu",
> +    [FW_CFG_MAX_CPUS] = "max_cpus",
> +    [FW_CFG_KERNEL_ENTRY] = "kernel_entry",
> +    [FW_CFG_KERNEL_DATA] = "kernel_data",
> +    [FW_CFG_INITRD_DATA] = "initrd_data",
> +    [FW_CFG_CMDLINE_ADDR] = "cmdline_addr",
> +    [FW_CFG_CMDLINE_SIZE] = "cmdline_size",
> +    [FW_CFG_CMDLINE_DATA] = "cmdline_data",
> +    [FW_CFG_SETUP_ADDR] = "setup_addr",
> +    [FW_CFG_SETUP_SIZE] = "setup_size",
> +    [FW_CFG_SETUP_DATA] = "setup_data",
> +    [FW_CFG_FILE_DIR] = "file_dir",
> +};
> +
> +void hmp_info_fw_cfg(Monitor *mon, const QDict *qdict)
> +{
> +    FWCfgState *s = fw_cfg_find();
> +    int arch, key;

Looks like this will crash on a machine without fw cfg.


> +
> +    monitor_printf(mon, "%12s %5s %7s %9s %6s %-24s\n",
> +                   "Type", "Perm", "Size", "Specific", "Order", "Info");
> +    for (arch = 0; arch < ARRAY_SIZE(s->entries); ++arch) {
> +        for (key = 0; key < fw_cfg_max_entry(s); ++key) {
> +            FWCfgEntry *e = &s->entries[arch][key];
> +            const char *perm = e->allow_write ? "RW" : "RO";
> +            const char *arch_spec = arch ? "arch_spec" : "";
> +            char *type, *info = NULL;
> +
> +            if (!e->len) {
> +                continue;
> +            }
> +            if (key >= FW_CFG_FILE_FIRST) {
> +                int id = key - FW_CFG_FILE_FIRST;
> +                const char *path = s->files->f[id].name;
> +
> +                type = g_strdup_printf("file (id %d)", id);
> +                monitor_printf(mon, "%12s %5s %7d %10s %5d %-24s\n",
> +                               type, perm, e->len, arch_spec,
> +                               get_fw_cfg_order(s, path), path);
> +                g_free(type);
> +                continue;
> +            }
> +            type = g_strdup(fw_cfg_wellknown_entries[key]);
> +            if (!type) {
> +                type = g_strdup_printf("entry_%d", key);
> +            }
> +
> +            switch (key) {
> +            case FW_CFG_SIGNATURE:
> +                info = g_strndup((const gchar *)e->data, e->len);
> +                break;
> +            case FW_CFG_UUID:
> +                info = qemu_uuid_unparse_strdup((const QemuUUID *)e->data);
> +                break;
> +            case FW_CFG_ID:
> +            case FW_CFG_NOGRAPHIC:
> +            case FW_CFG_NB_CPUS:
> +            case FW_CFG_BOOT_MENU:
> +            case FW_CFG_MAX_CPUS:
> +            case FW_CFG_RAM_SIZE:
> +            case FW_CFG_KERNEL_ADDR:
> +            case FW_CFG_KERNEL_SIZE:
> +            case FW_CFG_KERNEL_CMDLINE:
> +            case FW_CFG_KERNEL_ENTRY:
> +            case FW_CFG_KERNEL_DATA:
> +            case FW_CFG_INITRD_ADDR:
> +            case FW_CFG_INITRD_SIZE:
> +            case FW_CFG_INITRD_DATA:
> +            case FW_CFG_CMDLINE_ADDR:
> +            case FW_CFG_CMDLINE_SIZE:
> +            case FW_CFG_CMDLINE_DATA:
> +            case FW_CFG_SETUP_ADDR:
> +            case FW_CFG_SETUP_SIZE:
> +            case FW_CFG_SETUP_DATA:
> +                switch (e->len) {
> +                case 2:
> +                    info = g_strdup_printf("0x%04x", lduw_le_p(e->data));
> +                    break;
> +                case 4:
> +                    info = g_strdup_printf("0x%08x", ldl_le_p(e->data));
> +                    break;
> +                case 8:
> +                    info = g_strdup_printf("0x%016" PRIx64, ldq_le_p(e->data));
> +                    break;
> +                default:
> +                    break;
> +                }
> +                break;
> +            default:
> +                break;
> +            }
> +            monitor_printf(mon, "%12s %5s %7d %10s %5s %-24s\n",
> +                           type, perm, e->len, arch_spec, "", info ? info : "");
> +            g_free(type);
> +            g_free(info);
> +        }
> +    }
> +}
> diff --git a/include/hw/nvram/fw_cfg.h b/include/hw/nvram/fw_cfg.h
> index f5a6895a74..28630b2f26 100644
> --- a/include/hw/nvram/fw_cfg.h
> +++ b/include/hw/nvram/fw_cfg.h
> @@ -226,4 +226,6 @@ FWCfgState *fw_cfg_init_mem_wide(hwaddr ctl_addr,
>  FWCfgState *fw_cfg_find(void);
>  bool fw_cfg_dma_enabled(void *opaque);
>  
> +void hmp_info_fw_cfg(Monitor *mon, const QDict *qdict);
> +
>  #endif
> -- 
> 2.17.2