Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1946111AbbDXUgY (ORCPT ); Fri, 24 Apr 2015 16:36:24 -0400 Received: from out4-smtp.messagingengine.com ([66.111.4.28]:43978 "EHLO out4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966618AbbDXUgW (ORCPT ); Fri, 24 Apr 2015 16:36:22 -0400 X-Sasl-enc: JJxzAiB3QL2w9l8b9z0aNcYpWRrqoVW8rOSKcwGQB2lq 1429907780 Date: Fri, 24 Apr 2015 22:36:19 +0200 From: Greg KH To: Pantelis Antoniou Cc: Rob Herring , Grant Likely , Andrew Morton , Matt Porter , Koen Kooi , Guenter Roeck , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, Pantelis Antoniou Subject: Re: [PATCH v3 2/4] of: overlay: global sysfs enable attribute Message-ID: <20150424203619.GC14970@kroah.com> References: <1429868744-19863-1-git-send-email-pantelis.antoniou@konsulko.com> <1429868744-19863-3-git-send-email-pantelis.antoniou@konsulko.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1429868744-19863-3-git-send-email-pantelis.antoniou@konsulko.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1954 Lines: 59 On Fri, Apr 24, 2015 at 12:45:42PM +0300, Pantelis Antoniou wrote: > A throw once master enable switch to protect against any > further overlay applications if the administrator desires so. > > Signed-off-by: Pantelis Antoniou > --- > drivers/of/overlay.c | 45 ++++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 44 insertions(+), 1 deletion(-) > > diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c > index f17f5ef..c335809 100644 > --- a/drivers/of/overlay.c > +++ b/drivers/of/overlay.c > @@ -21,6 +21,7 @@ > #include > #include > #include > +#include > > #include "of_private.h" > > @@ -55,8 +56,12 @@ struct of_overlay { > struct kobject kobj; > }; > > +/* master enable switch; once set to 0 can't be re-enabled */ > +static atomic_t ov_enable = ATOMIC_INIT(1); > + > static int of_overlay_apply_one(struct of_overlay *ov, > struct device_node *target, const struct device_node *overlay); > +static int overlay_removal_is_ok(struct of_overlay *ov); > > static int of_overlay_apply_single_property(struct of_overlay *ov, > struct device_node *target, struct property *prop) > @@ -339,6 +344,37 @@ void of_overlay_release(struct kobject *kobj) > kfree(ov); > } > > +static ssize_t enable_show(struct kobject *kobj, > + struct kobj_attribute *attr, char *buf) > +{ > + return snprintf(buf, PAGE_SIZE, "%d\n", atomic_read(&ov_enable)); > +} > + > +static ssize_t enable_store(struct kobject *kobj, > + struct kobj_attribute *attr, const char *buf, size_t count) > +{ > + int ret; > + long new_enable; > + > + ret = kstrtol(buf, 10, &new_enable); strtobool()? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/