From: Karel Zak <kzak@redhat.com>
Date: Fri, 8 Jun 2018 09:37:55 +0000 (+0200)
Subject: blkzone: fix whole device detection
X-Git-Tag: v2.33-rc1~224
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ddf287b4eccdf23e5364e20e9a461fa89ccddf48;p=thirdparty%2Futil-linux.git

blkzone: fix whole device detection

Matias Bjørling wrote:
  The current detection code for chunk size assumes that the
  underlying device is a device that uses the minor device id
  as the partition id, and that the whole device has minor id 0.
  This is not true for example null_blk and nvme device drivers.

Let's use sysfs_devno_to_wholedisk() to get whole-disk devno.

Addresses: https://github.com/karelzak/util-linux/pull/646
Reported-by: Matias Bjørling matias.bjorling@wdc.com
Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/sys-utils/blkzone.c b/sys-utils/blkzone.c
index 6d837ff289..9c6dda0116 100644
--- a/sys-utils/blkzone.c
+++ b/sys-utils/blkzone.c
@@ -116,8 +116,7 @@ static unsigned long blkdev_chunk_sectors(const char *dname)
 {
 	struct sysfs_cxt cxt = UL_SYSFSCXT_EMPTY;
 	dev_t devno = sysfs_devname_to_devno(dname, NULL);
-	int major_no = major(devno);
-	int block_no = minor(devno) & ~0x0f;
+	dev_t disk;
 	uint64_t sz;
 	int rc;
 
@@ -126,8 +125,10 @@ static unsigned long blkdev_chunk_sectors(const char *dname)
 	 * This method masks off the partition specified by the minor device
 	 * component.
 	 */
-	devno = makedev(major_no, block_no);
-	if (sysfs_init(&cxt, devno, NULL))
+	if (sysfs_devno_to_wholedisk(devno, NULL, 0, &disk) != 0)
+		return 0;
+
+	if (sysfs_init(&cxt, disk, NULL))
 		return 0;
 
 	rc = sysfs_read_u64(&cxt, "queue/chunk_sectors", &sz);