From: Martin Wilck <mwilck@arcor.de>
Date: Tue, 30 Jul 2013 21:18:28 +0000 (+0200)
Subject: DDF: load_ddf_header: more error logging
X-Git-Tag: mdadm-3.3~55
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0e5fa86239cfa4cb5fbdbf46c14ddcb58708efc4;p=thirdparty%2Fmdadm.git

DDF: load_ddf_header: more error logging

Try to determine problem if load_ddf_header fails. May be useful
for determining compatibility problems with Fake RAID BIOSes.

Signed-off-by: Martin Wilck <mwilck@arcor.de>
Signed-off-by: NeilBrown <neilb@suse.de>
---

diff --git a/super-ddf.c b/super-ddf.c
index b639f07f..f55cc11b 100644
--- a/super-ddf.c
+++ b/super-ddf.c
@@ -754,18 +754,24 @@ static int load_ddf_header(int fd, unsigned long long lba,
 	if (read(fd, hdr, 512) != 512)
 		return 0;
 
-	if (!be32_eq(hdr->magic, DDF_HEADER_MAGIC))
+	if (!be32_eq(hdr->magic, DDF_HEADER_MAGIC)) {
+		pr_err("%s: bad header magic\n", __func__);
 		return 0;
-	if (!be32_eq(calc_crc(hdr, 512), hdr->crc))
+	}
+	if (!be32_eq(calc_crc(hdr, 512), hdr->crc)) {
+		pr_err("%s: bad CRC\n", __func__);
 		return 0;
+	}
 	if (memcmp(anchor->guid, hdr->guid, DDF_GUID_LEN) != 0 ||
 	    memcmp(anchor->revision, hdr->revision, 8) != 0 ||
 	    !be64_eq(anchor->primary_lba, hdr->primary_lba) ||
 	    !be64_eq(anchor->secondary_lba, hdr->secondary_lba) ||
 	    hdr->type != type ||
 	    memcmp(anchor->pad2, hdr->pad2, 512 -
-		   offsetof(struct ddf_header, pad2)) != 0)
+		   offsetof(struct ddf_header, pad2)) != 0) {
+		pr_err("%s: header mismatch\n", __func__);
 		return 0;
+	}
 
 	/* Looks good enough to me... */
 	return 1;