Re: [Xen-devel] [PATCH v2 2/5] xen: add generic flag to elf_dom_parms indicating support of unmapped initrd

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

On 02/10/15 06:49, Juergen Gross wrote:
> Support of an unmapped initrd is indicated by the kernel of the domain
> via elf notes. In order not to have to use raw elf data in the tools
> for support of an unmapped initrd add a flag to the parsed data area
> to indicate the kernel supporting this feature.
>
> Switch using this flag in the hypervisor domain builder.
>
> Cc: Keir Fraser <keir@xxxxxxx>
> Cc: Jan Beulich <jbeulich@xxxxxxxx>
> Cc: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> Cc: Tim Deegan <tim@xxxxxxx>
> Suggested-by: Ian Campbell <ian.campbell@xxxxxxxxxx>
> Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
> ---
>  xen/arch/x86/domain_build.c        | 4 ++--
>  xen/common/libelf/libelf-dominfo.c | 3 +++
>  xen/include/xen/libelf.h           | 1 +
>  3 files changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/xen/arch/x86/domain_build.c b/xen/arch/x86/domain_build.c
> index c2ef87a..a02c9fb 100644
> --- a/xen/arch/x86/domain_build.c
> +++ b/xen/arch/x86/domain_build.c
> @@ -353,7 +353,7 @@ static unsigned long __init compute_dom0_nr_pages(
>  
>          vstart = parms->virt_base;
>          vend = round_pgup(parms->virt_kend);
> -        if ( !parms->elf_notes[XEN_ELFNOTE_MOD_START_PFN].data.num )
> +        if ( !parms->mod_start_pfn )
>              vend += round_pgup(initrd_len);
>          end = vend + nr_pages * sizeof_long;
>  
> @@ -1037,7 +1037,7 @@ int __init construct_dom0(
>      v_start          = parms.virt_base;
>      vkern_start      = parms.virt_kstart;
>      vkern_end        = parms.virt_kend;
> -    if ( parms.elf_notes[XEN_ELFNOTE_MOD_START_PFN].data.num )
> +    if ( parms.mod_start_pfn )
>      {
>          vinitrd_start  = vinitrd_end = 0;
>          vphysmap_start = round_pgup(vkern_end);
> diff --git a/xen/common/libelf/libelf-dominfo.c 
> b/xen/common/libelf/libelf-dominfo.c
> index 3de1c23..31d8436 100644
> --- a/xen/common/libelf/libelf-dominfo.c
> +++ b/xen/common/libelf/libelf-dominfo.c
> @@ -190,6 +190,9 @@ elf_errorstatus elf_xen_parse_note(struct elf_binary *elf,
>      case XEN_ELFNOTE_INIT_P2M:
>          parms->p2m_base = val;
>          break;
> +    case XEN_ELFNOTE_MOD_START_PFN:
> +        parms->mod_start_pfn = !!val;
> +        break;
>      case XEN_ELFNOTE_PADDR_OFFSET:
>          parms->elf_paddr_offset = val;
>          break;
> diff --git a/xen/include/xen/libelf.h b/xen/include/xen/libelf.h
> index d7045f6..07b96a3 100644
> --- a/xen/include/xen/libelf.h
> +++ b/xen/include/xen/libelf.h
> @@ -423,6 +423,7 @@ struct elf_dom_parms {
>      char loader[16];
>      enum xen_pae_type pae;
>      bool bsd_symtab;
> +    bool mod_start_pfn;

The _pfn suffix here is confusing given the type of bool.

Perhaps "has_initrd" is a better choice of name?  The rest of the patch
looks fine.

~Andrew

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel