Initial DDF support code.

Create a ddf array by naming the device /dev/ddf* or
specifying metadata 'ddf'.

If ddf is specified with no level, assume a container (indeed,
anything else would be wrong).

**Need to use text_Version to set external metadata...

More ddf support

Load a ddf container.  Now
   --examine /dev/ddf
works.
super-ddf: fix compile warning

From: Dan Williams <dan.j.williams@intel.com>

super-ddf.c:723: format %lu expects type long unsigned int, but argument 3 has type unsigned int

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 51 insertions, 1 deletions

diff --git a/util.c b/util.c
index 733a466..a33486f 100644
--- a/util.c
+++ b/util.c
@@ -31,6 +31,7 @@
 #include	"md_p.h"
 #include	<sys/utsname.h>
 #include	<ctype.h>
+#include	<dirent.h>
 
 /*
  * following taken from linux/blkpg.h because they aren't
@@ -759,7 +760,7 @@ int dev_open(char *dev, int flags)
 	return fd;
 }
 
-struct superswitch *superlist[] = { &super0, &super1, NULL };
+struct superswitch *superlist[] = { &super0, &super1, &super_ddf, NULL };
 
 #if !defined(MDASSEMBLE) || defined(MDASSEMBLE) && defined(MDASSEMBLE_AUTO)
 struct supertype *super_by_fd(int fd)
@@ -908,6 +909,55 @@ void get_one_disk(int mdfd, mdu_array_info_t *ainf, mdu_disk_info_t *disk)
 			return;
 }
 
+int open_container(int fd)
+{
+	/* 'fd' is a block device.  Find out if it is in use
+	 * by a container, and return an open fd on that container.
+	 */
+	char path[256];
+	char *e;
+	DIR *dir;
+	struct dirent *de;
+	int dfd, n;
+	char buf[200];
+	int major, minor;
+	struct stat st;
+
+	if (fstat(fd, &st) != 0)
+		return -1;
+	sprintf(path, "/sys/dev/block/%d:%d/holders",
+		(int)major(st.st_rdev), (int)minor(st.st_rdev));
+	e = path + strlen(path);
+
+	dir = opendir(path);
+	if (!dir)
+		return -1;
+	while ((de = readdir(dir))) {
+		if (de->d_ino == 0)
+			continue;
+		if (de->d_name[0] == '.')
+			continue;
+		sprintf(e, "/%s/dev", de->d_name);
+		dfd = open(path, O_RDONLY);
+		if (dfd < 0)
+			continue;
+		n = read(dfd, buf, sizeof(buf));
+		close(dfd);
+		if (n <= 0 || n >= sizeof(buf))
+			continue;
+		buf[n] = 0;
+		if (sscanf(buf, "%d:%d", &major, &minor) != 2)
+			continue;
+		sprintf(buf, "%d:%d", major, minor);
+		dfd = dev_open(buf, O_RDONLY);
+		if (dfd >= 0) {
+			closedir(dir);
+			return dfd;
+		}
+	}
+	return -1;
+}
+
 #ifdef __TINYC__
 /* tinyc doesn't optimize this check in ioctl.h out ... */
 unsigned int __invalid_size_argument_for_IOC = 0;