[PATCH 1/4] lib: Add system config option to enable kexec_file_load

[Samuel Mendoza-Jonas]

On Thu, 2017-03-23 at 11:46 -0500, Eric Richter wrote:
> Currently, pb-discover only supports one method (syscall) for loading the
> next kernel for kexec: kexec_load. This patch adds a system configuration
> option for toggling between using kexec_load (false), and
> kexec_file_load (true).
> 
> This will be used in subsequent patches for determining the argument to
> kexec-lite/kexec-tools, and modified by a menu option.
> 
> Signed-off-by: Eric Richter <erichte at linux.vnet.ibm.com>
> ---
>  lib/pb-protocol/pb-protocol.c | 9 +++++++++
>  lib/types/types.h             | 2 ++
>  2 files changed, 11 insertions(+)
> 
> diff --git a/lib/pb-protocol/pb-protocol.c b/lib/pb-protocol/pb-protocol.c
> index 18edf57..a20bba9 100644
> --- a/lib/pb-protocol/pb-protocol.c
> +++ b/lib/pb-protocol/pb-protocol.c
> @@ -322,6 +322,8 @@ int pb_protocol_config_len(const struct config *config)
>  
>  	len += 4; /* allow_writes */
>  
> +	len += 4; /* kexec_method */
> +
>  	len += 4; /* n_consoles */
>  	for (i = 0; i < config->n_consoles; i++)
>  		len += 4 + optional_strlen(config->consoles[i]);
> @@ -582,6 +584,9 @@ int pb_protocol_serialise_config(const struct config *config,
>  	*(uint32_t *)pos = config->allow_writes;
>  	pos += 4;
>  
> +	*(uint32_t *)pos = config->kexec_method;
> +	pos += 4;
> +
>  	*(uint32_t *)pos = __cpu_to_be32(config->n_consoles);
>  	pos += 4;
>  	for (i = 0; i < config->n_consoles; i++)
> @@ -1121,6 +1126,10 @@ int pb_protocol_deserialise_config(struct config *config,
>  		goto out;
>  	config->allow_writes = !!tmp;
>  
> +	if (read_u32(&pos, &len, &tmp))
> +		goto out;
> +	config->kexec_method = !!tmp;
> +
>  	if (read_u32(&pos, &len, &config->n_consoles))
>  		goto out;
>  
> diff --git a/lib/types/types.h b/lib/types/types.h
> index 7f4ae1f..b21b2b2 100644
> --- a/lib/types/types.h
> +++ b/lib/types/types.h
> @@ -171,6 +171,8 @@ struct config {
>  
>  	bool			allow_writes;
>  
> +	bool			kexec_method;

A name like "kexec_secure" or "kexec_file_load" may be better - my
"kexec_method" being "true" sounds a bit confusing.

Patch 4 can probably also be squashed into this.

> +
>  	char			*boot_console;
>  	bool			manual_console;
>  	char			*lang;