Re: [PATCH v2 1/3] pseries: Make CPU hotplug path endian safe

[Nathan Fontenot <nfont@linux.vnet.ibm.com>]

On 09/16/2014 03:15 PM, Thomas Falcon wrote:
> From: Bharata B Rao <bharata@linux.vnet.ibm.com>
> 
> - ibm,rtas-configure-connector should treat the RTAS data as big endian.
> - Treat ibm,ppc-interrupt-server#s as big-endian when setting
>   smp_processor_id during hotplug.
> 
> Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
> Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>

Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>

> ---
> 
> Changes in v2:
> - Don't convert drc_index to BE in dlpar_configure_connector() but instead
>   convert in the caller dlpar_cpu_probe() so that migration path isn't
>   affected.
> - Mark members of cc_workarea struct as __be32 instead of u32 (Thomas)
> - Based on top of Thomas Falcon's two patches.
>   (http://patchwork.ozlabs.org/patch/388767/)
> 
> v1: http://patchwork.ozlabs.org/patch/386216/
> 
>  arch/powerpc/platforms/pseries/dlpar.c       | 22 +++++++++++-----------
>  arch/powerpc/platforms/pseries/hotplug-cpu.c |  4 ++--
>  arch/powerpc/platforms/pseries/pseries.h     |  3 ++-
>  3 files changed, 15 insertions(+), 14 deletions(-)
> 
> diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
> index a2450b8..5acbe59 100644
> --- a/arch/powerpc/platforms/pseries/dlpar.c
> +++ b/arch/powerpc/platforms/pseries/dlpar.c
> @@ -24,11 +24,11 @@
>  #include <asm/rtas.h>
>  
>  struct cc_workarea {
> -	u32	drc_index;
> -	u32	zero;
> -	u32	name_offset;
> -	u32	prop_length;
> -	u32	prop_offset;
> +	__be32	drc_index;
> +	__be32	zero;
> +	__be32	name_offset;
> +	__be32	prop_length;
> +	__be32	prop_offset;
>  };
>  
>  void dlpar_free_cc_property(struct property *prop)
> @@ -48,11 +48,11 @@ static struct property *dlpar_parse_cc_property(struct cc_workarea *ccwa)
>  	if (!prop)
>  		return NULL;
>  
> -	name = (char *)ccwa + ccwa->name_offset;
> +	name = (char *)ccwa + be32_to_cpu(ccwa->name_offset);
>  	prop->name = kstrdup(name, GFP_KERNEL);
>  
> -	prop->length = ccwa->prop_length;
> -	value = (char *)ccwa + ccwa->prop_offset;
> +	prop->length = be32_to_cpu(ccwa->prop_length);
> +	value = (char *)ccwa + be32_to_cpu(ccwa->prop_offset);
>  	prop->value = kmemdup(value, prop->length, GFP_KERNEL);
>  	if (!prop->value) {
>  		dlpar_free_cc_property(prop);
> @@ -78,7 +78,7 @@ static struct device_node *dlpar_parse_cc_node(struct cc_workarea *ccwa,
>  	if (!dn)
>  		return NULL;
>  
> -	name = (char *)ccwa + ccwa->name_offset;
> +	name = (char *)ccwa + be32_to_cpu(ccwa->name_offset);
>  	dn->full_name = kasprintf(GFP_KERNEL, "%s/%s", path, name);
>  	if (!dn->full_name) {
>  		kfree(dn);
> @@ -125,7 +125,7 @@ void dlpar_free_cc_nodes(struct device_node *dn)
>  #define CALL_AGAIN	-2
>  #define ERR_CFG_USE     -9003
>  
> -struct device_node *dlpar_configure_connector(u32 drc_index,
> +struct device_node *dlpar_configure_connector(__be32 drc_index,
>  					      struct device_node *parent)
>  {
>  	struct device_node *dn;
> @@ -411,7 +411,7 @@ static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
>  	if (!parent)
>  		return -ENODEV;
>  
> -	dn = dlpar_configure_connector(drc_index, parent);
> +	dn = dlpar_configure_connector(cpu_to_be32(drc_index), parent);
>  	if (!dn)
>  		return -EINVAL;
>  
> diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c
> index 20d6297..447f8c6 100644
> --- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
> +++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
> @@ -247,7 +247,7 @@ static int pseries_add_processor(struct device_node *np)
>  	unsigned int cpu;
>  	cpumask_var_t candidate_mask, tmp;
>  	int err = -ENOSPC, len, nthreads, i;
> -	const u32 *intserv;
> +	const __be32 *intserv;
>  
>  	intserv = of_get_property(np, "ibm,ppc-interrupt-server#s", &len);
>  	if (!intserv)
> @@ -293,7 +293,7 @@ static int pseries_add_processor(struct device_node *np)
>  	for_each_cpu(cpu, tmp) {
>  		BUG_ON(cpu_present(cpu));
>  		set_cpu_present(cpu, true);
> -		set_hard_smp_processor_id(cpu, *intserv++);
> +		set_hard_smp_processor_id(cpu, be32_to_cpu(*intserv++));
>  	}
>  	err = 0;
>  out_unlock:
> diff --git a/arch/powerpc/platforms/pseries/pseries.h b/arch/powerpc/platforms/pseries/pseries.h
> index 361add6..1796c54 100644
> --- a/arch/powerpc/platforms/pseries/pseries.h
> +++ b/arch/powerpc/platforms/pseries/pseries.h
> @@ -56,7 +56,8 @@ extern void hvc_vio_init_early(void);
>  /* Dynamic logical Partitioning/Mobility */
>  extern void dlpar_free_cc_nodes(struct device_node *);
>  extern void dlpar_free_cc_property(struct property *);
> -extern struct device_node *dlpar_configure_connector(u32, struct device_node *);
> +extern struct device_node *dlpar_configure_connector(__be32,
> +						struct device_node *);
>  extern int dlpar_attach_node(struct device_node *);
>  extern int dlpar_detach_node(struct device_node *);
>  
>