Re: [RFC v2 04/18] target/i386: sev: Embed SEVState in SevGuestState

[Philippe Mathieu-Daudé]

On 5/21/20 5:42 AM, David Gibson wrote:
> Currently SevGuestState contains only configuration information.  For
> runtime state another non-QOM struct SEVState is allocated separately.
> 
> Simplify things by instead embedding the SEVState structure in
> SevGuestState.
> 
> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
> ---
>  target/i386/sev.c | 54 +++++++++++++++++++++++++----------------------
>  1 file changed, 29 insertions(+), 25 deletions(-)
> 
> diff --git a/target/i386/sev.c b/target/i386/sev.c
> index b6ed719fb5..b4ab9720d6 100644
> --- a/target/i386/sev.c
> +++ b/target/i386/sev.c
> @@ -35,6 +35,22 @@
>  
>  typedef struct SevGuestState SevGuestState;
>  
> +struct SEVState {
> +    uint8_t api_major;
> +    uint8_t api_minor;
> +    uint8_t build_id;
> +    uint32_t policy;
> +    uint64_t me_mask;
> +    uint32_t cbitpos;
> +    uint32_t reduced_phys_bits;
> +    uint32_t handle;
> +    int sev_fd;
> +    SevState state;
> +    gchar *measurement;
> +};
> +
> +typedef struct SEVState SEVState;

Maybe typedef & declaration altogether.

> +
>  /**
>   * SevGuestState:
>   *
> @@ -48,6 +64,7 @@ typedef struct SevGuestState SevGuestState;
>  struct SevGuestState {
>      Object parent_obj;
>  
> +    /* configuration parameters */
>      char *sev_device;
>      uint32_t policy;
>      uint32_t handle;
> @@ -55,25 +72,11 @@ struct SevGuestState {
>      char *session_file;
>      uint32_t cbitpos;
>      uint32_t reduced_phys_bits;
> -};
>  
> -struct SEVState {
> -    SevGuestState *sev_info;
> -    uint8_t api_major;
> -    uint8_t api_minor;
> -    uint8_t build_id;
> -    uint32_t policy;
> -    uint64_t me_mask;
> -    uint32_t cbitpos;
> -    uint32_t reduced_phys_bits;
> -    uint32_t handle;
> -    int sev_fd;
> -    SevState state;
> -    gchar *measurement;
> +    /* runtime state */
> +    SEVState state;
>  };
>  
> -typedef struct SEVState SEVState;
> -
>  #define DEFAULT_GUEST_POLICY    0x1 /* disable debug */
>  #define DEFAULT_SEV_DEVICE      "/dev/sev"
>  
> @@ -506,12 +509,12 @@ sev_read_file_base64(const char *filename, guchar 
> **data, gsize *len)
>  }
>  
>  static int
> -sev_launch_start(SEVState *s)
> +sev_launch_start(SevGuestState *sev)
>  {
> +    SEVState *s = &sev->state;
>      gsize sz;
>      int ret = 1;
>      int fw_error, rc;
> -    SevGuestState *sev = s->sev_info;
>      struct kvm_sev_launch_start *start;
>      guchar *session = NULL, *dh_cert = NULL;
>  
> @@ -686,6 +689,7 @@ sev_vm_state_change(void *opaque, int running, RunState 
> state)
>  void *
>  sev_guest_init(const char *id)
>  {
> +    SevGuestState *sev;
>      SEVState *s;
>      char *devname;
>      int ret, fw_error;
> @@ -693,27 +697,27 @@ sev_guest_init(const char *id)
>      uint32_t host_cbitpos;
>      struct sev_user_data_status status = {};
>  
> -    sev_state = s = g_new0(SEVState, 1);
> -    s->sev_info = lookup_sev_guest_info(id);
> -    if (!s->sev_info) {
> +    sev = lookup_sev_guest_info(id);
> +    if (!sev) {
>          error_report("%s: '%s' is not a valid '%s' object",
>                       __func__, id, TYPE_SEV_GUEST);
>          goto err;
>      }
>  
> +    sev_state = s = &sev->state;

I was going to suggest to clean that, but I see your next patch already
does the cleanup :)

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

>      s->state = SEV_STATE_UNINIT;
>  
>      host_cpuid(0x8000001F, 0, NULL, &ebx, NULL, NULL);
>      host_cbitpos = ebx & 0x3f;
>  
> -    s->cbitpos = object_property_get_int(OBJECT(s->sev_info), "cbitpos", 
> NULL);
> +    s->cbitpos = object_property_get_int(OBJECT(sev), "cbitpos", NULL);
>      if (host_cbitpos != s->cbitpos) {
>          error_report("%s: cbitpos check failed, host '%d' requested '%d'",
>                       __func__, host_cbitpos, s->cbitpos);
>          goto err;
>      }
>  
> -    s->reduced_phys_bits = object_property_get_int(OBJECT(s->sev_info),
> +    s->reduced_phys_bits = object_property_get_int(OBJECT(sev),
>                                          "reduced-phys-bits", NULL);
>      if (s->reduced_phys_bits < 1) {
>          error_report("%s: reduced_phys_bits check failed, it should be >=1,"
> @@ -723,7 +727,7 @@ sev_guest_init(const char *id)
>  
>      s->me_mask = ~(1UL << s->cbitpos);
>  
> -    devname = object_property_get_str(OBJECT(s->sev_info), "sev-device", 
> NULL);
> +    devname = object_property_get_str(OBJECT(sev), "sev-device", NULL);
>      s->sev_fd = open(devname, O_RDWR);
>      if (s->sev_fd < 0) {
>          error_report("%s: Failed to open %s '%s'", __func__,
> @@ -754,7 +758,7 @@ sev_guest_init(const char *id)
>          goto err;
>      }
>  
> -    ret = sev_launch_start(s);
> +    ret = sev_launch_start(sev);
>      if (ret) {
>          error_report("%s: failed to create encryption context", __func__);
>          goto err;
>