Make get_component_size() work with named array.

get_component_size() still assumes that all array are
 /sys/block/md%d or /sys/block/md_d%d
and so doesn't work with e.g. /sys/block/md_foo.

This cause "mdadm --detail" to report
   Used Dev Size : unknown
and causes problems when added spares and in other circumstances.

So change it to use stat2devnm() which does the right thing with all
types of array names.

Reported-and-tested-by: Robert LeBlanc <robert@leblancnet.us>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>

diff --git a/sysfs.c b/sysfs.c
index 84c7348526c995929a2d7f07b68ee801d3363529..b0657a04b3a3270aa0059223197815dc4c1a49a7 100644 (file)
--- a/sysfs.c
+++ b/sysfs.c
@@ -400,14 +400,8 @@ unsigned long long get_component_size(int fd)
        int n;
        if (fstat(fd, &stb))
                return 0;
        int n;
        if (fstat(fd, &stb))
                return 0;

-       if (major(stb.st_rdev) != (unsigned)get_mdp_major())
-               snprintf(fname, MAX_SYSFS_PATH_LEN,
-                       "/sys/block/md%d/md/component_size",
-                       (int)minor(stb.st_rdev));
-       else
-               snprintf(fname, MAX_SYSFS_PATH_LEN,
-                       "/sys/block/md_d%d/md/component_size",
-                       (int)minor(stb.st_rdev)>>MdpMinorShift);
+       snprintf(fname, MAX_SYSFS_PATH_LEN,
+                "/sys/block/%s/md/component_size", stat2devnm(&stb));

        fd = open(fname, O_RDONLY);
        if (fd < 0)
                return 0;
        fd = open(fname, O_RDONLY);
        if (fd < 0)
                return 0;