From: Jes Sorensen <Jes.Sorensen@gmail.com>
Date: Thu, 30 Mar 2017 20:02:36 +0000 (-0400)
Subject: sysfs: Use the presence of /sys/block/<dev>/md as indicator of valid device
X-Git-Tag: mdadm-4.1-rc1~218
X-Git-Url: http://git.ipfire.org/?p=thirdparty%2Fmdadm.git;a=commitdiff_plain;h=67a02d520085b01a1b9e6ea59fb30e79c5649c9c;ds=sidebyside

sysfs: Use the presence of /sys/block/<dev>/md as indicator of valid device

Rather than calling ioctl(RAID_VERSION), use the presence of
/sys/block/<dev>/md as indicator of the device being valid and sysfs
being active for it. The ioctl could return valid data, but sysfs
not mounted, which renders sysfs_init() useless anyway.

Signed-off-by: Jes Sorensen <Jes.Sorensen@gmail.com>
---

diff --git a/sysfs.c b/sysfs.c
index 2a91ba0a..93ec3de8 100644
--- a/sysfs.c
+++ b/sysfs.c
@@ -86,15 +86,22 @@ void sysfs_init_dev(struct mdinfo *mdi, unsigned long devid)
 
 void sysfs_init(struct mdinfo *mdi, int fd, char *devnm)
 {
+	struct stat stb;
+	char fname[MAX_SYSFS_PATH_LEN];
+
 	mdi->sys_name[0] = 0;
-	if (fd >= 0) {
-		mdu_version_t vers;
-		if (ioctl(fd, RAID_VERSION, &vers) != 0)
-			return;
+	if (fd >= 0)
 		devnm = fd2devnm(fd);
-	}
+
 	if (devnm == NULL)
 		return;
+
+	snprintf(fname, MAX_SYSFS_PATH_LEN, "/sys/block/%s/md", devnm);
+
+	if (stat(fname, &stb))
+		return;
+	if (!S_ISDIR(stb.st_mode))
+		return;
 	strcpy(mdi->sys_name, devnm);
 }