From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:54847) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gyzcB-00040P-IG for qemu-devel@nongnu.org; Wed, 27 Feb 2019 08:51:16 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gyzcA-0000lL-Oh for qemu-devel@nongnu.org; Wed, 27 Feb 2019 08:51:15 -0500 Received: from mail-qt1-f194.google.com ([209.85.160.194]:39843) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1gyzcA-0000kw-Ii for qemu-devel@nongnu.org; Wed, 27 Feb 2019 08:51:14 -0500 Received: by mail-qt1-f194.google.com with SMTP id o6so19191211qtk.6 for ; Wed, 27 Feb 2019 05:51:14 -0800 (PST) Date: Wed, 27 Feb 2019 08:51:11 -0500 From: "Michael S. Tsirkin" Message-ID: <20190227084843-mutt-send-email-mst@kernel.org> References: <20190226073159.13434-1-richardw.yang@linux.intel.com> <20190226110934-mutt-send-email-mst@kernel.org> <20190227053319.GB5449@richard> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190227053319.GB5449@richard> Subject: Re: [Qemu-devel] [PATCH] fw_cfg: use __ATTR_RO_MODE to define rev sysfs List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Wei Yang Cc: qemu-devel@nongnu.org, linux-kernel@vger.kernel.org, somlo@cmu.edu On Wed, Feb 27, 2019 at 01:33:19PM +0800, Wei Yang wrote: > On Tue, Feb 26, 2019 at 11:10:06AM -0500, Michael S. Tsirkin wrote: > >On Tue, Feb 26, 2019 at 03:31:59PM +0800, Wei Yang wrote: > >> Leverage __ATTR_RO_MODE to define rev sysfs instead of using open code > >> to define the attribute. > >> > >> Signed-off-by: Wei Yang > >> --- > >> drivers/firmware/qemu_fw_cfg.c | 13 ++++--------- > >> 1 file changed, 4 insertions(+), 9 deletions(-) > >> > >> diff --git a/drivers/firmware/qemu_fw_cfg.c b/drivers/firmware/qemu_fw_cfg.c > >> index 039e0f91dba8..a1293cbd7adb 100644 > >> --- a/drivers/firmware/qemu_fw_cfg.c > >> +++ b/drivers/firmware/qemu_fw_cfg.c > >> @@ -296,18 +296,13 @@ static int fw_cfg_do_platform_probe(struct platform_device *pdev) > >> return 0; > >> } > >> > >> -static ssize_t fw_cfg_showrev(struct kobject *k, struct attribute *a, char *buf) > >> +static ssize_t fw_cfg_rev_show(struct kobject *k, struct kobj_attribute *a, > >> + char *buf) > >> { > >> return sprintf(buf, "%u\n", fw_cfg_rev); > >> } > >> - > >> -static const struct { > >> - struct attribute attr; > >> - ssize_t (*show)(struct kobject *k, struct attribute *a, char *buf); > >> -} fw_cfg_rev_attr = { > >> - .attr = { .name = "rev", .mode = S_IRUSR }, > >> - .show = fw_cfg_showrev, > >> -}; > >> +static const struct kobj_attribute fw_cfg_rev_attr = > >> + __ATTR_RO_MODE(fw_cfg_rev, 0400); > >> > >> /* fw_cfg_sysfs_entry type */ > >> struct fw_cfg_sysfs_entry { > > > > > >Looks like this will change the name from "rev" to "fw_cfg_rev". > >That's a userspace visible change which we should not do lightly. > > You are right, I should keep the interface untouched. > > To keep it user un-visible, we could change like below: > > - __ATTR_RO(fw_cfg_rev); > + __ATTR_RO(rev); > > Is this better for you? Also why use 0400 and not S_IRUSR? > >> -- > >> 2.19.1 > > -- > Wei Yang > Help you, Help me