+static int update_raid_disks(mddev_t *mddev, int raid_disks);
+
+static ssize_t
+raid_disks_store(mddev_t *mddev, const char *buf, size_t len)
+{
+ /* can only set raid_disks if array is not yet active */
+ char *e;
+ int rv = 0;
+ unsigned long n = simple_strtoul(buf, &e, 10);
+
+ if (!*buf || (*e && *e != '\n'))
+ return -EINVAL;
+
+ if (mddev->pers)
+ rv = update_raid_disks(mddev, n);
+ else
+ mddev->raid_disks = n;
+ return rv ? rv : len;
+}
+static struct md_sysfs_entry md_raid_disks =
+__ATTR(raid_disks, 0644, raid_disks_show, raid_disks_store);
+
+static ssize_t
+chunk_size_show(mddev_t *mddev, char *page)
+{
+ return sprintf(page, "%d\n", mddev->chunk_size);
+}
+
+static ssize_t
+chunk_size_store(mddev_t *mddev, const char *buf, size_t len)
+{
+ /* can only set chunk_size if array is not yet active */
+ char *e;
+ unsigned long n = simple_strtoul(buf, &e, 10);
+
+ if (mddev->pers)
+ return -EBUSY;
+ if (!*buf || (*e && *e != '\n'))
+ return -EINVAL;
+
+ mddev->chunk_size = n;
+ return len;
+}
+static struct md_sysfs_entry md_chunk_size =
+__ATTR(chunk_size, 0644, chunk_size_show, chunk_size_store);
+
+
+static ssize_t
+size_show(mddev_t *mddev, char *page)
+{
+ return sprintf(page, "%llu\n", (unsigned long long)mddev->size);
+}
+
+static int update_size(mddev_t *mddev, unsigned long size);
+
+static ssize_t
+size_store(mddev_t *mddev, const char *buf, size_t len)
+{
+ /* If array is inactive, we can reduce the component size, but
+ * not increase it (except from 0).
+ * If array is active, we can try an on-line resize
+ */
+ char *e;
+ int err = 0;
+ unsigned long long size = simple_strtoull(buf, &e, 10);
+ if (!*buf || *buf == '\n' ||
+ (*e && *e != '\n'))
+ return -EINVAL;
+
+ if (mddev->pers) {
+ err = update_size(mddev, size);
+ md_update_sb(mddev);
+ } else {
+ if (mddev->size == 0 ||
+ mddev->size > size)
+ mddev->size = size;
+ else
+ err = -ENOSPC;
+ }
+ return err ? err : len;
+}
+
+static struct md_sysfs_entry md_size =
+__ATTR(component_size, 0644, size_show, size_store);
+
+
+/* Metdata version.
+ * This is either 'none' for arrays with externally managed metadata,
+ * or N.M for internally known formats
+ */
+static ssize_t
+metadata_show(mddev_t *mddev, char *page)
+{
+ if (mddev->persistent)
+ return sprintf(page, "%d.%d\n",
+ mddev->major_version, mddev->minor_version);
+ else
+ return sprintf(page, "none\n");
+}
+
+static ssize_t
+metadata_store(mddev_t *mddev, const char *buf, size_t len)
+{
+ int major, minor;
+ char *e;
+ if (!list_empty(&mddev->disks))
+ return -EBUSY;
+
+ if (cmd_match(buf, "none")) {
+ mddev->persistent = 0;
+ mddev->major_version = 0;
+ mddev->minor_version = 90;
+ return len;
+ }
+ major = simple_strtoul(buf, &e, 10);
+ if (e==buf || *e != '.')
+ return -EINVAL;
+ buf = e+1;
+ minor = simple_strtoul(buf, &e, 10);
+ if (e==buf || *e != '\n')
+ return -EINVAL;
+ if (major >= sizeof(super_types)/sizeof(super_types[0]) ||
+ super_types[major].name == NULL)
+ return -ENOENT;
+ mddev->major_version = major;
+ mddev->minor_version = minor;
+ mddev->persistent = 1;
+ return len;
+}
+
+static struct md_sysfs_entry md_metadata =
+__ATTR(metadata_version, 0644, metadata_show, metadata_store);