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From: Huaisheng Ye <yehs2007@zoho.com>
To: linux-nvdimm@lists.01.org, dan.j.williams@intel.com
Cc: jack@suse.cz, snitzer@redhat.com, heiko.carstens@de.ibm.com,
	dm-devel@redhat.com, agk@redhat.com, linux-s390@vger.kernel.org,
	willy@infradead.org, bart.vanassche@wdc.com,
	keescook@chromium.org, chengnt@lenovo.com, colyli@suse.de,
	schwidefsky@de.ibm.com, viro@zeniv.linux.org.uk, axboe@kernel.dk,
	gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
	linux-fsdevel@vger.kernel.org
Subject: [PATCH v3 2/6] s390, dcssblk: kaddr and pfn can be NULL to ->direct_access()
Date: Mon, 30 Jul 2018 15:15:44 +0800	[thread overview]
Message-ID: <20180730071548.9172-3-yehs2007@zoho.com> (raw)
In-Reply-To: <20180730071548.9172-1-yehs2007@zoho.com>

From: Huaisheng Ye <yehs1@lenovo.com>

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.

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.

Signed-off-by: Huaisheng Ye <yehs1@lenovo.com>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 drivers/s390/block/dcssblk.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

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;
 
 	dev_sz = dev_info->end - dev_info->start + 1;
-	*kaddr = (void *) dev_info->start + offset;
-	*pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset),
-			PFN_DEV|PFN_SPECIAL);
+	if (kaddr)
+		*kaddr = (void *) dev_info->start + offset;
+	if (pfn)
+		*pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset),
+				PFN_DEV|PFN_SPECIAL);
 
 	return (dev_sz - offset) / PAGE_SIZE;
 }
-- 
1.8.3.1


_______________________________________________
Linux-nvdimm mailing list
Linux-nvdimm@lists.01.org
https://lists.01.org/mailman/listinfo/linux-nvdimm

WARNING: multiple messages have this Message-ID (diff)
From: Huaisheng Ye <yehs2007@zoho.com>
To: linux-nvdimm@lists.01.org, dan.j.williams@intel.com
Cc: ross.zwisler@linux.intel.com, willy@infradead.org,
	vishal.l.verma@intel.com, dave.jiang@intel.com,
	schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com,
	viro@zeniv.linux.org.uk, martin.petersen@oracle.com,
	axboe@kernel.dk, gregkh@linuxfoundation.org,
	bart.vanassche@wdc.com, jack@suse.cz, agk@redhat.com,
	snitzer@redhat.com, keescook@chromium.org, dm-devel@redhat.com,
	linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org,
	linux-fsdevel@vger.kernel.org, colyli@suse.de,
	chengnt@lenovo.com, Huaisheng Ye <yehs1@lenovo.com>
Subject: [PATCH v3 2/6] s390, dcssblk: kaddr and pfn can be NULL to ->direct_access()
Date: Mon, 30 Jul 2018 15:15:44 +0800	[thread overview]
Message-ID: <20180730071548.9172-3-yehs2007@zoho.com> (raw)
In-Reply-To: <20180730071548.9172-1-yehs2007@zoho.com>

From: Huaisheng Ye <yehs1@lenovo.com>

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.

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.

Signed-off-by: Huaisheng Ye <yehs1@lenovo.com>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 drivers/s390/block/dcssblk.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

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;
 
 	dev_sz = dev_info->end - dev_info->start + 1;
-	*kaddr = (void *) dev_info->start + offset;
-	*pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset),
-			PFN_DEV|PFN_SPECIAL);
+	if (kaddr)
+		*kaddr = (void *) dev_info->start + offset;
+	if (pfn)
+		*pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset),
+				PFN_DEV|PFN_SPECIAL);
 
 	return (dev_sz - offset) / PAGE_SIZE;
 }
-- 
1.8.3.1



WARNING: multiple messages have this Message-ID (diff)
From: Huaisheng Ye <yehs2007-ytc+IHgoah0@public.gmane.org>
To: linux-nvdimm-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org,
	dan.j.williams-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org
Cc: jack-AlSwsSmVLrQ@public.gmane.org,
	snitzer-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org,
	heiko.carstens-tA70FqPdS9bQT0dZR+AlfA@public.gmane.org,
	dm-devel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org,
	agk-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org,
	linux-s390-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	willy-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org,
	bart.vanassche-Sjgp3cTcYWE@public.gmane.org,
	keescook-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org,
	chengnt-6jq1YtArVR3QT0dZR+AlfA@public.gmane.org,
	colyli-l3A5Bk7waGM@public.gmane.org,
	schwidefsky-tA70FqPdS9bQT0dZR+AlfA@public.gmane.org,
	viro-RmSDqhL/yNMiFSDQTTA3OLVCufUGDwFn@public.gmane.org,
	axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org,
	gregkh-hQyY1W1yCW8ekmWlsbkhG0B+6BGkLq7r@public.gmane.org,
	linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: [PATCH v3 2/6] s390, dcssblk: kaddr and pfn can be NULL to ->direct_access()
Date: Mon, 30 Jul 2018 15:15:44 +0800	[thread overview]
Message-ID: <20180730071548.9172-3-yehs2007@zoho.com> (raw)
In-Reply-To: <20180730071548.9172-1-yehs2007-ytc+IHgoah0@public.gmane.org>

From: Huaisheng Ye <yehs1-6jq1YtArVR3QT0dZR+AlfA@public.gmane.org>

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.

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.

Signed-off-by: Huaisheng Ye <yehs1-6jq1YtArVR3QT0dZR+AlfA@public.gmane.org>
Reviewed-by: Ross Zwisler <ross.zwisler-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
Acked-by: Martin Schwidefsky <schwidefsky-tA70FqPdS9bQT0dZR+AlfA@public.gmane.org>
---
 drivers/s390/block/dcssblk.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

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;
 
 	dev_sz = dev_info->end - dev_info->start + 1;
-	*kaddr = (void *) dev_info->start + offset;
-	*pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset),
-			PFN_DEV|PFN_SPECIAL);
+	if (kaddr)
+		*kaddr = (void *) dev_info->start + offset;
+	if (pfn)
+		*pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset),
+				PFN_DEV|PFN_SPECIAL);
 
 	return (dev_sz - offset) / PAGE_SIZE;
 }
-- 
1.8.3.1

  parent reply	other threads:[~2018-07-30  7:16 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-07-30  7:15 [PATCH v3 0/6] kaddr and pfn can be NULL to ->direct_access() Huaisheng Ye
2018-07-30  7:15 ` Huaisheng Ye
2018-07-30  7:15 ` Huaisheng Ye
2018-07-30  7:15 ` [PATCH v3 1/6] libnvdimm, pmem: " Huaisheng Ye
2018-07-30  7:15   ` Huaisheng Ye
2018-07-30  7:15   ` Huaisheng Ye
2018-07-30  7:15 ` Huaisheng Ye [this message]
2018-07-30  7:15   ` [PATCH v3 2/6] s390, dcssblk: " Huaisheng Ye
2018-07-30  7:15   ` Huaisheng Ye
2018-07-30  7:15 ` [PATCH v3 3/6] tools/testing/nvdimm: " Huaisheng Ye
2018-07-30  7:15   ` Huaisheng Ye
2018-07-30  7:15   ` Huaisheng Ye
2018-07-30  7:15 ` [PATCH v3 4/6] dax/super: Do not request a pointer kaddr when not required Huaisheng Ye
2018-07-30  7:15   ` Huaisheng Ye
2018-07-30  7:15   ` Huaisheng Ye
2018-07-30  7:15 ` [PATCH v3 5/6] md/dm-writecache: Don't request pointer dummy_addr " Huaisheng Ye
2018-07-30  7:15   ` Huaisheng Ye
2018-07-30  7:15   ` Huaisheng Ye
2018-07-30  7:15 ` [PATCH v3 6/6] filesystem-dax: Do not request kaddr and pfn " Huaisheng Ye
2018-07-30  7:15   ` Huaisheng Ye
2018-07-30  7:15   ` Huaisheng Ye
2018-07-30  7:30 ` [External] [PATCH v3 0/6] kaddr and pfn can be NULL to ->direct_access() Huaisheng HS1 Ye
2018-07-30  7:30   ` Huaisheng HS1 Ye
2018-07-30  7:30   ` Huaisheng HS1 Ye
2018-07-31 15:35 ` Dave Jiang
2018-07-31 15:35   ` Dave Jiang

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