Subject: Re: [PATCH v2 1/1] of: reform prom_update_property function

From: Benjamin Herrenschmidt <[email-masked]>
Date: Mon, 25 Jun 2012 16:46:38 +1000

On Mon, 2012-06-25 at 14:28 +0800, Dong Aisheng wrote:
> From: Dong Aisheng <[email-masked]>
> 
> prom_update_property() currently fails if the property doesn't
> actually exist yet which isn't what we want. Change to add-or-update
> instead of update-only, then we can remove a lot duplicated lines.
> 
> Suggested-by: Grant Likely <[email-masked]>
> Signed-off-by: Dong Aisheng <[email-masked]>
> ---

Grand, should I merge that via the powerpc tree or will you take care of
it ?

Acked-by: Benjamin Herrenschmidt <[email-masked]>

Cheers,
Ben.

> ChangeLog v1->v2:
> * keep reconfig.c behavior the same as before after changes
> ---
>  arch/powerpc/platforms/85xx/p1022_ds.c    |    8 +-------
>  arch/powerpc/platforms/pseries/mobility.c |    8 +-------
>  arch/powerpc/platforms/pseries/reconfig.c |   16 ++++++----------
>  drivers/of/base.c                         |   15 +++++++++++----
>  fs/proc/proc_devtree.c                    |    5 +++++
>  include/linux/of.h                        |    3 +--
>  6 files changed, 25 insertions(+), 30 deletions(-)
> 
> diff --git a/arch/powerpc/platforms/85xx/p1022_ds.c b/arch/powerpc/platforms/85xx/p1022_ds.c
> index f700c81..d66631c 100644
> --- a/arch/powerpc/platforms/85xx/p1022_ds.c
> +++ b/arch/powerpc/platforms/85xx/p1022_ds.c
> @@ -348,13 +348,7 @@ void __init p1022_ds_pic_init(void)
>   */
>  static void __init disable_one_node(struct device_node *np, struct property *new)
>  {
> -	struct property *old;
> -
> -	old = of_find_property(np, new->name, NULL);
> -	if (old)
> -		prom_update_property(np, new, old);
> -	else
> -		prom_add_property(np, new);
> +	prom_update_property(np, new);
>  }
>  
>  /* TRUE if there is a "video=fslfb" command-line parameter. */
> diff --git a/arch/powerpc/platforms/pseries/mobility.c b/arch/powerpc/platforms/pseries/mobility.c
> index 029a562..dd30b12 100644
> --- a/arch/powerpc/platforms/pseries/mobility.c
> +++ b/arch/powerpc/platforms/pseries/mobility.c
> @@ -67,7 +67,6 @@ static int update_dt_property(struct device_node *dn, struct property **prop,
>  			      const char *name, u32 vd, char *value)
>  {
>  	struct property *new_prop = *prop;
> -	struct property *old_prop;
>  	int more = 0;
>  
>  	/* A negative 'vd' value indicates that only part of the new property
> @@ -117,12 +116,7 @@ static int update_dt_property(struct device_node *dn, struct property **prop,
>  	}
>  
>  	if (!more) {
> -		old_prop = of_find_property(dn, new_prop->name, NULL);
> -		if (old_prop)
> -			prom_update_property(dn, new_prop, old_prop);
> -		else
> -			prom_add_property(dn, new_prop);
> -
> +		prom_update_property(dn, new_prop);
>  		new_prop = NULL;
>  	}
>  
> diff --git a/arch/powerpc/platforms/pseries/reconfig.c b/arch/powerpc/platforms/pseries/reconfig.c
> index 7b3bf76..db1b7b1 100644
> --- a/arch/powerpc/platforms/pseries/reconfig.c
> +++ b/arch/powerpc/platforms/pseries/reconfig.c
> @@ -432,7 +432,7 @@ static int do_update_property(char *buf, size_t bufsize)
>  	unsigned char *value;
>  	char *name, *end, *next_prop;
>  	int rc, length;
> -	struct property *newprop, *oldprop;
> +	struct property *newprop;
>  	buf = parse_node(buf, bufsize, &np);
>  	end = buf + bufsize;
>  
> @@ -443,6 +443,9 @@ static int do_update_property(char *buf, size_t bufsize)
>  	if (!next_prop)
>  		return -EINVAL;
>  
> +	if (!strlen(name)
> +		return -ENODEV;
> +
>  	newprop = new_property(name, length, value, NULL);
>  	if (!newprop)
>  		return -ENOMEM;
> @@ -450,18 +453,11 @@ static int do_update_property(char *buf, size_t bufsize)
>  	if (!strcmp(name, "slb-size") || !strcmp(name, "ibm,slb-size"))
>  		slb_set_size(*(int *)value);
>  
> -	oldprop = of_find_property(np, name,NULL);
> -	if (!oldprop) {
> -		if (strlen(name))
> -			return prom_add_property(np, newprop);
> -		return -ENODEV;
> -	}
> -
>  	upd_value.node = np;
>  	upd_value.property = newprop;
>  	pSeries_reconfig_notify(PSERIES_UPDATE_PROPERTY, &upd_value);
>  
> -	rc = prom_update_property(np, newprop, oldprop);
> +	rc = prom_update_property(np, newprop);
>  	if (rc)
>  		return rc;
>  
> @@ -486,7 +482,7 @@ static int do_update_property(char *buf, size_t bufsize)
>  
>  		rc = pSeries_reconfig_notify(action, value);
>  		if (rc) {
> -			prom_update_property(np, oldprop, newprop);
> +			prom_update_property(np, newprop);
>  			return rc;
>  		}
>  	}
> diff --git a/drivers/of/base.c b/drivers/of/base.c
> index d9bfd49..a14f109 100644
> --- a/drivers/of/base.c
> +++ b/drivers/of/base.c
> @@ -1051,7 +1051,8 @@ int prom_remove_property(struct device_node *np, struct property *prop)
>  }
>  
>  /*
> - * prom_update_property - Update a property in a node.
> + * prom_update_property - Update a property in a node, if the property does
> + * not exist, add it.
>   *
>   * Note that we don't actually remove it, since we have given out
>   * who-knows-how-many pointers to the data using get-property.
> @@ -1059,13 +1060,19 @@ int prom_remove_property(struct device_node *np, struct property *prop)
>   * and add the new property to the property list
>   */
>  int prom_update_property(struct device_node *np,
> -			 struct property *newprop,
> -			 struct property *oldprop)
> +			 struct property *newprop)
>  {
> -	struct property **next;
> +	struct property **next, *oldprop;
>  	unsigned long flags;
>  	int found = 0;
>  
> +	if (!newprop->name)
> +		return -EINVAL;
> +
> +	oldprop = of_find_property(np, newprop->name, NULL);
> +	if (!oldprop)
> +		return prom_add_property(np, newprop);
> +
>  	write_lock_irqsave(&devtree_lock, flags);
>  	next = &np->properties;
>  	while (*next) {
> diff --git a/fs/proc/proc_devtree.c b/fs/proc/proc_devtree.c
> index 927cbd1..df7dd08 100644
> --- a/fs/proc/proc_devtree.c
> +++ b/fs/proc/proc_devtree.c
> @@ -101,6 +101,11 @@ void proc_device_tree_update_prop(struct proc_dir_entry *pde,
>  {
>  	struct proc_dir_entry *ent;
>  
> +	if (!oldprop) {
> +		proc_device_tree_add_prop(pde, newprop);
> +		return;
> +	}
> +
>  	for (ent = pde->subdir; ent != NULL; ent = ent->next)
>  		if (ent->data == oldprop)
>  			break;
> diff --git a/include/linux/of.h b/include/linux/of.h
> index 2ec1083..b27c871 100644
> --- a/include/linux/of.h
> +++ b/include/linux/of.h
> @@ -260,8 +260,7 @@ extern int of_machine_is_compatible(const char *compat);
>  extern int prom_add_property(struct device_node* np, struct property* prop);
>  extern int prom_remove_property(struct device_node *np, struct property *prop);
>  extern int prom_update_property(struct device_node *np,
> -				struct property *newprop,
> -				struct property *oldprop);
> +				struct property *newprop);
>  
>  #if defined(CONFIG_OF_DYNAMIC)
>  /* For updating the device tree at runtime */