+#ifndef __UBOOT__
+static int
+concat_writev(struct mtd_info *mtd, const struct kvec *vecs,
+ unsigned long count, loff_t to, size_t * retlen)
+{
+ struct mtd_concat *concat = CONCAT(mtd);
+ struct kvec *vecs_copy;
+ unsigned long entry_low, entry_high;
+ size_t total_len = 0;
+ int i;
+ int err = -EINVAL;
+
+ /* Calculate total length of data */
+ for (i = 0; i < count; i++)
+ total_len += vecs[i].iov_len;
+
+ /* Check alignment */
+ if (mtd->writesize > 1) {
+ uint64_t __to = to;
+ if (do_div(__to, mtd->writesize) || (total_len % mtd->writesize))
+ return -EINVAL;
+ }
+
+ /* make a copy of vecs */
+ vecs_copy = kmemdup(vecs, sizeof(struct kvec) * count, GFP_KERNEL);
+ if (!vecs_copy)
+ return -ENOMEM;
+
+ entry_low = 0;
+ for (i = 0; i < concat->num_subdev; i++) {
+ struct mtd_info *subdev = concat->subdev[i];
+ size_t size, wsize, retsize, old_iov_len;
+
+ if (to >= subdev->size) {
+ to -= subdev->size;
+ continue;
+ }
+
+ size = min_t(uint64_t, total_len, subdev->size - to);
+ wsize = size; /* store for future use */
+
+ entry_high = entry_low;
+ while (entry_high < count) {
+ if (size <= vecs_copy[entry_high].iov_len)
+ break;
+ size -= vecs_copy[entry_high++].iov_len;
+ }
+
+ old_iov_len = vecs_copy[entry_high].iov_len;
+ vecs_copy[entry_high].iov_len = size;
+
+ err = mtd_writev(subdev, &vecs_copy[entry_low],
+ entry_high - entry_low + 1, to, &retsize);
+
+ vecs_copy[entry_high].iov_len = old_iov_len - size;
+ vecs_copy[entry_high].iov_base += size;
+
+ entry_low = entry_high;
+
+ if (err)
+ break;
+
+ *retlen += retsize;
+ total_len -= wsize;
+
+ if (total_len == 0)
+ break;
+
+ err = -EINVAL;
+ to = 0;
+ }
+
+ kfree(vecs_copy);
+ return err;
+}
+#endif
+