From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail1.bemta24.messagelabs.com ([67.219.250.115]:32055 "EHLO mail1.bemta24.messagelabs.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726047AbeG1Fco (ORCPT ); Sat, 28 Jul 2018 01:32:44 -0400 From: Huaisheng HS1 Ye To: "linux-s390@vger.kernel.org" , "schwidefsky@de.ibm.com" , "heiko.carstens@de.ibm.com" , "bart.vanassche@wdc.com" , "martin.petersen@oracle.com" , "axboe@kernel.dk" , "keescook@chromium.org" CC: "ross.zwisler@linux.intel.com" , "willy@infradead.org" , "vishal.l.verma@intel.com" , "dave.jiang@intel.com" , "viro@zeniv.linux.org.uk" , "gregkh@linuxfoundation.org" , "jack@suse.cz" , "agk@redhat.com" , "snitzer@redhat.com" , "dm-devel@redhat.com" , "linux-kernel@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" , "NingTing Cheng" , "colyli@suse.de" , Huaisheng Ye , "linux-nvdimm@lists.01.org" , "dan.j.williams@intel.com" Subject: RE: [External] [PATCH v2 2/6] s390, dcssblk: kaddr and pfn can be NULL to ->direct_access() Date: Sat, 28 Jul 2018 04:07:25 +0000 Message-ID: References: <20180725162849.8320-1-yehs2007@zoho.com> <20180725162849.8320-3-yehs2007@zoho.com> In-Reply-To: <20180725162849.8320-3-yehs2007@zoho.com> Content-Language: zh-CN Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Dear Maintainers of Linux-s390, Greetings. May I have your ack's for this patch? The whole series would be applied to libnvdimm if it could get your approval. And any suggestion is welcome. Cheers, Huaisheng Ye > From: Huaisheng Ye > Sent: Thursday, July 26, 2018 12:29 AM >=20 > From: Huaisheng Ye >=20 > dcssblk_direct_access() needs to check the validity of pointers kaddr > and pfn for NULL assignment. If anyone equals to NULL, it doesn't need > to calculate the value. >=20 > If either of them is equal to NULL, that is to say callers may > have no need for kaddr or pfn, so this patch is prepared for allowing > them to pass in NULL instead of having to pass in a pointer or local > variable that they then just throw away. >=20 > Signed-off-by: Huaisheng Ye > --- > drivers/s390/block/dcssblk.c | 8 +++++--- > 1 file changed, 5 insertions(+), 3 deletions(-) >=20 > diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c > index ed60728..23e526c 100644 > --- a/drivers/s390/block/dcssblk.c > +++ b/drivers/s390/block/dcssblk.c > @@ -922,9 +922,11 @@ static DEVICE_ATTR(save, S_IWUSR | S_IRUSR, dcssblk_= save_show, > unsigned long dev_sz; >=20 > dev_sz =3D dev_info->end - dev_info->start + 1; > - *kaddr =3D (void *) dev_info->start + offset; > - *pfn =3D __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset), > - PFN_DEV|PFN_SPECIAL); > + if (kaddr) > + *kaddr =3D (void *) dev_info->start + offset; > + if (pfn) > + *pfn =3D __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset), > + PFN_DEV|PFN_SPECIAL); >=20 > return (dev_sz - offset) / PAGE_SIZE; > } > -- > 1.8.3.1